I honestly don't know which is the tougher fight for Conor. It seems like Tony is the ideal candidate to reproduce the Diaz-style winning formula of surviving the early onslaught and then using cardio and length to get to him once he slows a little. Tony is also very slick on the ground and can kick and check kicks. Khabib seems like he could take the Mendes-style path to victory and actually see it through. They will both have issues in the stand up early in the fight. The question is who overcomes it more readily. I think Khabib probably, since he just needs to get a hold of Conor and the fight is on the mat the rest of that round. However, if he has trouble getting a hold of Conor, he is a fish out of water against Conor. Tony can at least make it tough for Conor early with his length, chin and better striking defense and offense than Khabib has.