Which Machamp to power up

IMO the only Machamp that MAYBE worth powering up is Karate Chop/Cross Chop. I have a Karate Chop/Stone Edge one 93.3% and will not power it up. Since that candies are not a problem, i would just wait for the best moveset before spend some dust.

Karate Chop + Submission does work on Lapras

I have a few karate chop submissions. I use them vs snorlax but don't really like them particularly because of the animation. It seems to glitch sometimes and I can no longer see the defender or when he'll attack

kc gets stab, but is weak and resisted by all machamp's counters (alakazam, exeg, drag, pidgeot). bp is stronger, but no stab and resisted by common attackers; vape and arcanine. Bp is probably better over all for defence, but not much to pick between them imo.
I would choose the submission one however; as the more time spent using submission, the less time spent using those poor quick moves.