Disagree completely. My pro4(which I have offered for sale to vazzo btw) was by far the best 540 car I have raced, by a long way. It has an easily maintained and very free driveline, especially with the upgrade single piece gearbox shafts, and can also quite easily take the smaller 65ish teeth pinion gears and monster pinions(48dpi) that get you the right gearing/rollout for 540 running. It may be out of it's depth with the new low wind brushless motors(too much torque steer) but for lower power classes is still a competitive chassis. Most of the regularly broken bits are interchangable with a cyclone and are pretty cheap and easy to obtain also.

I only stopped using it when I started running stock as I did not like how it drove when fitted with a front diff(best front axle type for newbs on my local carpet track) and I loved the quality of the xray cars I moved onto, but not the second mortage needed to run the things.