Dude, Man-Ape stomps. Unless I'm missing something here.
Gorilla Man is a dude that got transformed into a normal, but an immortal (not dying of NATURAL CAUSES), gorilla (meaning he has the stats of your average Silverback Gorilla).
Man-Ape is an actual SUPERHUMAN man/beast. He's stronger and more durable than Gorilla Man.
PS : Cool thread idea.
On paper, yes. But GM's feats put him above that --- headbutting Wolvie, kicking Rock of the Buddha's (whose strength was compared to that of Thing) ass for some time. He also carries high-tech weapons with him from time to time, so there's always that if no other options are viable.
We should always analyze matches carefully, otherwise someone like Batman would get stomped in 99% matches against more-than-peak-human characters.
I also wanted to learn of some of M'Baku's actual feats 😛