Then put it this way,

Make the weight class 2.4gig and if someone new turns up with a 27meg car, a robosapien or a furby then it's up to the event organiser as to whether or not it runs, in most cases I can't see a problem but I don't see any point in taking a step back technology wise. Especially when a 2.4gig set can be picked up for less than a 40meg set. PLEASE SOMEONE MAKE A ROBOTIC MOVING FURBY!!!