I got this for myself as a birthday present, and it has not disappointed! I had lusted after OhMiBod's musical vibrators for ages. And when I finally got my black NaughtiBod in the mail, I couldn't wait to try it out. I immediately put the batteries in (it came with batteries! We like that!) and plugged the cord into my computer headphone jack. I popped open iTunes to see what would work best. I just held it in one hand, while holding the mouse with the other, dragging stuff onto a playlist as I went.
When bedtime came, it was time to try it out for real. I synced my playlist, slid a condom over the toy, slicked everything up, and went to town. I'll admit, I'm the kind of girl who likes to be filled completely, so this was a new kind of sensation for me, but dear heaven. I wouldn't trade this little wonder for anything. It's only 1" around, which makes insertion a breeze. But the curves give it this added bit of sensation that drove me absolutely wild. It took me no time at all to find just the right angle for this to tap-dance all over my G-Spot, and make me writhe.
One downside is you do have to keep the volume high for the vibrator to work properly. But if you set it too high, it will just go at a constant hum rather than going with the music. Depending on what you're listening to, I found that 65 to 80% of the volume works best. It didn't kill my ears, at any rate. You do have to pick something with a good bass line or it won't register a whole lot. It also seems to be really picky about what sounds it wants to acknowledge, but I managed to put together a playlist that takes me all the way from "just warming up" to "explosion". There's a remix out there that combines Cascada with Lady Gaga that has never failed to take me to the top!
I suppose it could also be used as a clitoral vibrator, but it's a little too soft for my clit, since I like focused vibration there. Don't let that stop you if you want to use it that way, though!
Not clear what you mean about the music and regular caps but I'm sure the product review will answer this question.