I have a ROMEO 1.0 board mounted on a cheap 10x toy rc truck, which I am using for the basic experiments (Rock Crawler unassembled in cupboard until experiments mature a little).
I took the RC gear out of the truck, including the clunky left-right only steering. I am replacing the steering for a RC sail boat servo which has 360 degree rotation (1x) – rather than 180 degree of the standard servo. It also comes with a pully so I can use it to provide proportional steering to the chassis.
PWM experiments disappointing so far. The toy status causes a problem as the gearing is quite high, so once juice enough to turn the wheels, it lurches ahead quite fast.