Really? I mean, I can understand the pain of having to replace the batteries, but that aside, I really can't see how the gimmick items having their own electronics is worse than ones that don't really add anything to the toy.
I just don't like the feeling that I'm buying more toys to unlock the sounds of the toy that I already bought. Not to mention, unlike gimmicks which have their own electronics, they're pretty much locked into whatever they pre-programed onto the belt. No changes, no extras, no specials. Any new features will have to be put into a newer release like the Mobirates or the White Wizard Driver, necessitating the re-purchase of a new belt.