My friend runs either High Jump Kick/Zen Headbutt/Fire Punch/Ice Punch or High Jump Kick/Zen Headbutt/Foresight/Ice Punch, since he finds the priority to be disappointing for Medicham, and it's worked pretty well for him. He's good enough to reach the 1760+ range on the ladder, so it seems that he's found a way to manage.
I never ran Genesect in OU, I think at that point, I started to just wait and see if they would eventually ban it from OU since I just wanted it gone. And since physically based is a lot more useful in Ubers, I've never had more than one or two special moves.
They're both threatening, but Genesect was always tougher for me to beat. That, and I ran into Genesect much more than I ran into Mega Lucario.