wargreymon, if you are considering all incarnation. wargreymon burst mode and the complete crimson version of the burst deigivolution called firegreymon{or watever it was} that defeated yggdrasil would own any version of normal wargreymon. also the god version of wargreymon which was created by yygdrassil as on of its failsafes revealed in the battle against barbmon wud also destroy any metalgarurumon.
Maybe he's talking about Wargreymon X-Antibody.
Anyways, Wargreymon is more maneuverable and obviously more powerful physically.(lifted a house up; Puppetmon's house)
However, i'll give Metalgarurumon the speed advantage, since he has the Blue-Digizoid, which allows to fly at tremendous speeds. Wargreymon would also need to watch out for Metalgarurumon's 'Cocytus Breath' since it reaches absolute zero.
But overall, i'll give it to Wargreymon.
Hmm how would he be Omegamon lvl?
In Digimon x evolution Wargreymon X was able to fight Omegamon without getting his butt raped. I honestly thought he did well agasint Omegamon.
He also has some good durability like when Omegamon blasted him through like 5 or so mountains(or large mesas) and he didnt even have a scratch on him.
Lol i think we need a Digimon Vs. Digimon thread. To settle this kind of off-topic fights.