Hardest pinion

My buggy eats pinions. I've rc monster motor mount, well mounted without any movement and my gear mesh is good but my buggy keep eating pinions. Especially after some jumps pinions begin to deforming and after 2-3 weeks they are totally dead. My buggy is a hyper 8 with regular center diff and steel spur gear. I tried mikes pinions and they didn't hold up too:(
I'm considering to get robinson or ofna. Which one would be more durable?