best weapon for mm!? help

m60 4 mm but rpk is best for everything else!

Rpk is good also in other modes.M60 isn't good on position where you have to run if Mutants Overrun(like in port on the ramp) with an RPk you can run away and push down mutants,M60 is heavier and have less recoil but an higher Bullet Spread.RPK is faster to reload,have a more knockdown but less damage.M60 is VERY GOOD against mutants trapped in a corner,70 ammo(alone) in short distance and he's dead.
With an RPK you need support to take 'em down,so i suggest the RPK gold.

Final opinion: there's no supreme weapon,you can use better an RPK or an M60,feel free to choose.If you have 180K GP or more buy both,and try them.