Nice that it finally got noticed.
Once I'd already hacked up my IR Rod racer, I found one of those pen cars. It has a switch and PCB layout that are a LOT better for this application. The pen racer was like 12, and the IR Rod is currently on clearance at RS.
Here are the new body guts.
Playing with it some yesterday, I realized that part of the ZZ-m board had popped. (an inductor in the reciever circuitry) So now I'm eyeing little cars with bad intentions... (StuntCars and MuscleMachines are supposed to have dual h-bridge boards)