Duke is specifically designed as an insertable vibrating prostate massager, and it does a good job at it. The interior arm is bulgy and long, designed to make the Duke feel more "filling" then other vibrating massagers as well as helping the Duke stay in place on its own. As it is made out of soft silicone, the Duke is easy to insert and is comfortable in almost any position.The Duke's vibrator pocket is sized to fit the included rechargeable 3-speed + 3-pattern vibrator, and is located in the insertable arm for enhanced internal stimulation. Because the vibrator is not waterproof minor care needs to be exercised during use and cleaning to keep the bullet from getting wet, but other than that the Duke is a well-designed, reliable toy with a silicone body for safety and cleanliness.

Once the Duke is inserted you don't need to do anything beyond turning it on. In most positions the Duke stays put on its own, and the vibrations are distributed well across the entire toy, though there is a bias towards internal stimulation. Should you or your partner want to take a more active role you can manipulate the Duke by hand or using your pubic muscles to vary the stimulation.. The vibrations are mid-strength and pleasantly rumbly, but even on high they are not quite earth shattering, and the battery life is adequate at about 20 minutes of constant use on high, my favorite setting. During use the vibrator is relatively quiet and the sound that it does emit is low pitched and not very penetrating, so you can use the Duke in areas of slightly limited privacy.

The extended internal arm of the Duke means that it may be a bit uncomfortable for G-spot use, but it can be run along the labia and clitoris of a woman if desired.

The main body of the Duke is made out of Fun Factory's matte-finished soft silicone. In common with all of Fun Factory's other silicone toys, the Duke is unscented and tasteless. Except for the part stiffened by the vibrator, Duke is soft to the touch and slightly squishy, and the silicone surface easily grabs dust or your skin if it isn't lubricated. The texture is generally smooth, with several strategic bulges to increase stimulation and help it to stay in place during use.

The design of the Duke Click 'n' Charge is good for most people. While the middle prostate "bloop" requires a bit more relaxation to insert than a straight toy would, the Duke's maximum (asymmetric) diameter of 1.25" x 1" is attainable by almost anyone. I found the shape and design very comfortable and stimulating, and the Duke's design enables Fun Factory to deliver a product that is both stimulating and soft at the same time. The soft material is great because it enables the toy to conform to your inner curves rather than fighting with them, while the design ensures that it puts a pleasurable amount of pressure and vibrations right on your prostate.

Fun Factory's good design extends to other little things as well, such as the small cutaway at the edge that makes it easier to access the power button and the Click 'n' Charge system. The Click 'n' Charge setup makes use of a magnetically attached charging adapter that snaps on to two metal hemispheres on the removable bullet. It is convenient and functional, though you do need to be careful if the toy might be around loose metal such as paperclips, as they can be attracted and potentially short out the terminals.

The discretion of the Duke is limited. While the blue or black silicone can hide away in the shadows, it would take a great deal of balls to pass it off as a piece of modern art if it gets noticed. The charger is even less discreet - the wall plug is emblazoned "Love yourself", and the Click 'n' Charge end not only says "Fun Factory" in white letters, but those letters light up when the charger is in use. This toy is best kept in a private place both for use and storage.

The performance of the Duke was very impressive. Duke does a very good job of staying put without being held in by hand. I was able to stand, sit, or lie down without Duke slipping out, and though several times it felt as though it was slipping out it never actually did. The only time I had a problem keeping Duke in was when I tried to use it while squatting, and even then the upper "bloop" kept the toy from coming all the way out.

Duke was also more than satisfactory as a vibrator. While the larger-than-standard diameter Click 'n' Charge vibrator bullet limits your options for using replacement or aftermarket vibrators in Duke, the included vibrator works well. I have used it for over twenty minutes on a charge without much fading, and charging is reasonably fast and convenient. The external vibrations at the perineum are noticeable and pleasant, albeit much more "surface level" than the vibrations at the main body which are nice and throbby. In contrast, on many other vibrating prostate massagers with a rear-mounted vibe the perineum arm stops vibrating easily if it is up against something, whereas the perineum attachment on Duke quiets down a bit but keeps going.

The vibrator has three settings: low, medium, high and three speeds of pulse. They are selected by pressing the on-off button to toggle between them. To turn the Duke off you need to hold the button down for one second, so you're less likely to inadvertently turn the vibrator off. I found the vibration balance on the high setting to be very nice, a deeper, more rumbly vibration than many bullets offer that felt very good against the prostate. It did seem that the choice of patterns was more optimized for clitoral use, as I didn't notice much of a difference in the patterns when Duke was against my prostate.

The Duke requires a bit of care during use and cleaning. While the body is made out of durable silicone, the vibrating bullet is not waterproof. This leads to a little bit of difficulty for cleanup as the bullet must be removed before washing.

Fortunately the removable vibrator is easy to take out, and once that is done the silicone body of the Duke can be easily cleaned in the sink, wiped off, or even run through the dishwasher. Afterwards the body can be sanitized by boiling or 10% bleach solution. The non-waterproof bullet requires a bit more care, as it will need to be cleaned off from time to time, but it cannot be put in the water. A damp washcloth or similar method is probably the best way to clean the vibrator, but it's best to avoid trying to sanitize it as bleach might corrode the contacts.

After use it's a good idea to charge the batteries, both so it is ready to go the next time you want to use Duke as well as to make sure the batteries stay in top condition. Other than this (and keeping it away from metal because of the magnetic terminals), the Duke is easy to store. It will be comfortable in almost any toybox.

Because of the silicone body construction and the non-waterproof vibrator it's probably best to stick with water-based lubes, as these are guaranteed not to react with the silicone material of the body and they can be easily cleaned up. While oil-based lubes could be used (and some silicone lubes may be safe, but do test first), it is much harder to remove oil or silicone lubes from the bullet without risking getting water in the vibrator.

The Duke Click 'n' Charge comes in two boxes. The first box is an ordinary paper box that holds the charging adapter and is decorated with pictures of the various toys that use the Click 'n' Charge system. The second box holds Duke itself, and has a clear window and Fun Factory's magnetically-locked fold-out cover that offers some information on the toy. Inside the box there is a slide-out cardboard tray that holds the Duke, a more detailed instruction sheet, a catalog of the various Fun Factory toys, and a sample of Toyfluid lubricant. The Toyfluid is a thin water-based lube that is paraben free.

As with all Fun Factory boxes, the design is classy and subdued enough so you can use it as a gift box for anyone you'd give a sex toy to. There are no nude or semi-nude pictures, just a photograph of the Duke and some line drawings showing the toy and how it fits during use. Because it is made of cardboard it probably is not durable enough for long-term storage of the Duke, but it can be recycled.

In general I like the Duke. The throbby vibrations are very nice, and they're both concentrated right on the prostate where they need to be as well as being noticeable at the perineum. This doesn't mean that the Duke is perfect, there are some things that really should be done.

The first is a waterproof vibrator. Sure, you can get the Duke's bullet out much easier then the bullet used on the Nexus Ridge Rider, but you still need to be careful during use and cleaning. A waterproof vibe would make things much easier. Secondly, I found that I really only used the "high" setting. I imagine that someone less familiar to prostate stimulation might like one of the lower settings, but the patterns did very little for me. I found that one of the Nexus' patterns was much more interesting, although of the Duke's patterns my favorite was the last (high, pulsating, slowly getting faster over about 4 seconds). I do really like the deeper, "throbby" vibrations for prostate stimulation, as they carry very well through my whole pelvic area.

How does the Duke compare to the "Boy" vibrators from Rocks Off? I found several differences. Firstly, the Duke did a better job of staying in place than any of the Rocks Off toys I have. While the Cheeky Boy will stay in, I do need to "hold" it in with my anus, whereas the Duke stays put with a more relaxed anus (though it feels like it's popping out it didn't in most positions).The "Boy" stimluators are made of stiffer silicone, so they put more pressure on the prostate, whereas the Duke relies more on the vibrating. Duke isn't a weakling, though, as the extended internal arm helps to keep it pressed up against the prostate, just not quite as firmly.
The vibrations are also different between Duke and the "Boys". Duke's vibrations are more throbby, and the vibrator is mounted up just inside the anus. The Boys have vibrators mounted right at the perineum, so the vibration is stronger there, and the vibrators are a bit "buzzier" than the Duke's vibe.