The Tamiya TRF 501X is a hugely strong and reliable car - but one or two small things have prevented me from winning several times this season. The wheel nuts - as stupid as it sounds, were one of the biggest issues for me. The serrated Hot Bodies nuts stayed on the car, and a quick 'tweak' before each race, which I'd become accustomed to doing, was never needed.
The anodising is probably as good as it gets, but the torque needed to remove the nuts, coupled with the rough 'Tamiya' tool I was using, means the nuts get quickly scratched up. Perhaps a raw alloy coloured nut could be offered in future?
The only 'issue' with these babies is when something else goes wrong with the car. Twice I have had a front wheel strip out from using the one-way diff on high traction surfaces - and this stripped wheel will rapidly loosen the wheelnut, allowing the wheel to strip even more and come flying off the car. It's a small point, but worth mentioning - don't even think of using these with a front wheel that's in less than great shape.
A review on WHEEL NUTS! These are a seriously great upgrade however, so don't dismiss!