I got this drum because it's cheap and I thought maybe at least something about it would be fun to mess around with. I have an ion, but my pedal is too loud and I also wanted to get something I could take with me on the go to a friends' house. Well this thing worked as well as the other reviewers have said. The pedal in this kit is better and makes less impact noise than any pedal on the market, and if you can stick the pads down in one place, they seem to work perfectly as well. The only downside is that you pretty much have to use this with the included sticks, because the pads are too hard. The sticks in the box are rubber to compensate. Using wooden sticks on these is too loud to stand.
Another added perk of this kit is that the controller can be plugged in standalone and used like an NES controller for arcade games, as long as the games don't use the shoulder buttons. Also, people who are interested in modding projects can use the little controller part as the "brain" for a custom drum kit. People have used this to turn their nice electronic kits into RB kits!
Let me reiterate again that the pedal on this is better than the stock ion pedal in terms of noise and equal in function. Get a 1/4" to 1/8" converter and use it with your ion.
In every way, this product is worth your money if you're looking for any of the above features.
ADDITION: I am adding this to the review as a caution: the sticks that this comes with seem to be susceptible to breaking at the middle where they screw together. Now, I know that all drum sticks break eventually, but just be prepared to try to locate some rubber-head sticks as backups because you really can't play this too well with a wooden head.
UPDATE 6/29/09: The pedal for this is still working great, and I still use it with my expensive Ion drum kit. I play on expert now better than ever, and this pedal is very accurate and much easier to double tap to get those super-rapid beats. The official pedal I bought recently doesn't respond well at all to quick rapid pushes like this does. I even got a second portable kit just so I could have a spare, and the second one works just as well.