So, I am running a RX 520 chain, and in the off season, it's on my list of parts to change out. I did some reading about chains, and found one site (I'll try and find the exact link) that stated the application (IE dirt, street, race etc) is pretty much BS, and one should look at tensile strength above all when buying one.
With this in mind, I have found numerous "dirt/MX" chains in 520 pitch that appear to have higher tensile strength than many "street/race" marketed chains. Also, the MX chains are loads cheaper than the street/race chains.
When looking at individual chain maker's web sites, I see alot in terms of proper application..."not to exceed 250cc" etc. However, many that say not to exceed smaller displacement bikes seem to have some higher tensile strength than some higher displacement machines.
My question is, do you guys/gals run chains marketed as "MX/dirt" on your race bikes? If so, what type (chain) and what application? $50 vs. $120 would be nice.....

Cheers,
Ski