[Staxman]

I had the problem with the drive shafts snapping
I replaced them with Losi 22 shafts and (touch wood) they have been fine since.
The only other things that I have changed are the springs because, as commented on earlier, the kit ones are a bit rubbish, and I have switched the rear hex's to the slightly wider losi aluminium ones.
The car works a treat...I would agree with the other contributors, don't make changes for the sake of it (apart from the springs), wait until something breaks then change it, because out of the box the car is really good...especially if you are like me and coming back to the sport after about 22 years away from buggy racing.