there are a lot of cheap ripoffs out there but the bottom line here is that if you want quality (you don't want to pay though your teeth) you have to do your homework
check out auldeys new mini-z ... it has full proprtional steering and throttle and looks a lot like kyosho's mini-z but has a larger body and use AA batteries ... retails for about $40 on carmoworld.com ... not bad for a fully proportional car (proportional control not size) ... and auldey quality and durability is quite good (better than the cheap knockoffs but below kyosho mini-z's) ... haven't got one yet but i've heard good things