personally i don't use metal spurs on my vehicles. i like to keep a metal/plastic/metal/plastic design philosophy. if you start running metal on metal, there's no 'give' in the drive train. when the plastic spurs give out it's because something bad is happening and that is the weak point in the system. if you run a metal spur, it won't give out but something else will. usually it's a harder to get to more expensive part. make sure your mesh is set correctly ( i always use the dollar bill method) and you'll be able to run plastic spurs with no problems. besides, at less than $4 for a replacement it's easy to keep a few extras on hand, just in case.