I have worked on a -fun- kart racing sim years ago and wrote everything with C-Script and in the first place it is really the easier route to go. But even though it had simplified physics, I didn't got it right and had problems everywhere: on the one side I tried to make it more realistic, but on the other side I always had trouble with the car alignment on the floor and the behaviour in mid air (like driving over ramps). But if you things like "whirling on bananas" and bombs and such stuff, it could be tricky do do it well with a physics-driven vehicle setup, yes.

Well, I guess it all depends on the requirements you have and how you want your physics simulation in the end.

If you advanced, sure, call me, why not.

Here is already one best practice I can give you from what I learned from my PhysX coding sessions: when defining positions and hinge axis directions and so on, try to place bones in your model and access them via their names. This is much more convenient and customizable than defining offsets and such via skills, like in the current vehicle templates.

[EDIT]

@3run: I wonder if the turret is an attached physics object (reacting on vehicle momentum and crashes and so on) or if it is attached as a seperate model (or via bone animation?). If the former, I wonder how they translate the crosshair direction into runtime constraint-parameters?