It's been mentioned in a couple other threads... the 2.4ghz HengLong radios and more specifically the T-34 (only model that I've read about people noticing..) when you steer and move forward, the inside track does not slow down gradually. It just stops.

So you can't make gentle, wide turns. It's very jerky and messy and you have to be very quick on the control stick... it sucks basically.