[smokes]

Basically ball diff act like an Limited slip diff on an road car how much slip depend on how much you tighten the diff. With the gear diff it act like and open diff as soon as on e wheel lift of the ground the power goes to the unloaded wheel. With modern tooling and seals we can now use heavy silicon fluid to stop the gear diff unloading to the undriven wheel.

The only difference is the weight of the gear diff means if has more inertia to over come than a ball diff, hence it slower to accelarate, but with the torque of a brushless it is not noticable.

But the gear diff won't slip when accelarting in a straight line like a ball diff will due limit of how tight you have the diff plate before it flattens the balls and stops it working.

how it feels i don't know as i haven't used a fluid filled gear diff yet.