Hi Jason,
The trailing arms work well on dirt tracks. Used to run them here in the UK when we had dirt tracks, same with the gearbox. The gear box was designed for dirt, it gets up to speed very quickly and helps with braking. On a high grip (grass or astro) the belt drive prevents the car from rolling off throttle, it's almost like having drag brake but on dusty dirt it works really well. Years ago when I met Chris Alec he explained the thought behind the design.
One point, the diff plates needs some work on polishing to get them nice & smooth but once polished they are smooth as butter. The power clutch worked well, very adjustable.
Hope this helps.
