I finally got to play this game. Is it a good game? Yes. Is it worth the investment? I don't know.
There's something about the combat that bothers me. The enemies seem slippery, it feels like things never quite hit their mark, I can't quite explain it.
The animations are good, and I know that the exaggeration and the somewhat "rubbery" look is an animation technique, but it definitely doesn't suit the Sentinels – especially the giant Sentinel that stomps on you. It looks like an old washing machine that starts rattling when you turn it on, haha.
And without giving spoilers, I found the story a bit disjointed, even though it tries to follow the comics in some points. There are much bigger challenges than the final boss that you face before him (and which are even harder than the final boss).
My favorite character: Iron Man. And I use either Ghost Raider or Beta Ray Bill as a partner.
Characters I hated: Phoenix.