Wonderman at the top of his game is probably Englehart written Wonderman. I'd have said his stronger than Masterson due to his fight with Thor but a writer's cock stroking can only take you so far. Hyperion had Wonderman's ass beat an issue after the Thor fight. Looking at that, I'd easily come to the conclusion that Thor simply held back but whatever. Masterson also looked clearly superior to Wonderman in their fight against Gladiator about 3 years later.
If Englehart was writing this, I'd have said Wonderman is superior physically but would lose due to Masterson's other powers. Dude wanted Wonderman to be stronger than Thor and the Hulk, and tried his best to show it.