Let's get the big question out of the way: Does it really look like a spaceship? Well, no it doesn't. =D

The "Doc Joc's Incredible Jack-Off Device" is a 4"-long, 2"-wide plastic tube that has a 1.5" TPR sleeve, a rubber squeeze ball, and a bullet-type vibrator. The sleeve can be reversed for either smooth or nubby texture. The use of the squeeze ball provides movement along the shaft. The vibrator is intended to add stimulation. The sleeve, tube, and rubber ball can all be washed with warm water and soap.

The overall build quality is good. Nothing feels fragile about this device. The weight felt better (read more manageable) without the vibrator, but certainly not unusable with the vibrator on-board.
Since there are no instructions (as mentioned by another reviewer), I'll elaborate a bit more in the "Experience" section.

When my mentor (woohoo Antipova!) suggested this as review piece, I thought it would be a great candidate. With two totally opposite ratings, I thought I could help be the deciding factor. Unfortunately, I land squarely in the middle. I liked using the toy, but it never drove me to orgasm. The vibrator base doesn't fit as squarely as designed when the bullet is placed in the intended holder. It fits great as displayed in the product picture, but you'll notice the bullet is not centered. I found the vibrator to be less effective when the bullet was off-center.

Addressing the vibration, it was incredibly mezzo-mezzo for me. It didn't really add to the experience, but it didn't detract either.

As I'm a huge fan of playing in the shower, I completely removed the vibrator when giving it a ride in the shower (just a little CYA there...). My experience there was about the same as every other experience I've had with this--one big "Meh."

I liked the movement generated by the squeeze ball and I found regulating the speed of stroke to be pretty easy once I got a feel for the squeeze ball. I didn't have the issue with the ball sliding off as reported in one of the other reviews.

So these are my not-close-to-official instructions for using the device.
Attaching the sleeve

Insert one end of the sleeve into the toy. I inserted to almost where the bullet-holder juts inward.
Stretch the outside opening of the sleeve and fold over the outside of the cylinder. The molded area that holds the vibrator base will prevent you from going too far (less than an inch).
You notice that there's some doubled-up sleeve outside of the cylinder. This is as expected.

Getting Started
Apply some lube.
Squeeze and hold the bulb.
Insert cock. *Remember that this is going to pull you (and some of the doubled-up liner) in when you release the ball.*

From there, it's completely up to you.

Functionally, when you insert your rod, you are creating a seal and there is a finite amount of air. Releasing the bulb forces the air into the bulb and pulls you right in. Squeezing the ball will force that air into the cylinder. If you are stationary, the cylinder will move away from you. If the cylinder is stationary, you (perhaps in a semi-erect state) will bear the movement. If both you and the cylinder are stationary, some of the air will escape somehow. ;)

It still comes out of the toy box occasionally, but it's pretty rare and only when I've got a hankering for it.