Ok... I've got both. I've only played Heros a lil. I like UA. Anyone else have any opinions?

Justice League Heroes is the shiznit. Ive beaten it 3 times so far, got every character unlocked plus each variant costume.

Haven't played JLH yet,I enjoyed Ultimate Alliance although I was a bit disappointed in it in the sense that I expected more than just Xmen Legends with different marvel characters. Its still a good,fun game though.

I plan on getting marvel UA when i see it going cheap.Kind of gutted that there are exclusive characters for different machines,i'd love to play as moon knight.

Darkseid is the final boss on JLH, he is tough as hell. You have to defeat him 3 times. It took me a while to beat him, but after I did it was easier the second and third times around.