ok, this is a good question... there was much hype leading up to the "epic" crossover a few years back to the abortion of a story the companies gave it... so i will throw my opinion in. if you go with the classic matchups of avengers (giant man, wasp, THOR, hulk, iron man, and cap even though they didnt thaw him out till later) vs the jla (supes, bats, flash, wonder woman, green lantern, aquaman, martian manhunter)... i would regretfully have to say the jla, just because dc comics is all about revamping characters with new and greater powers every few years, while marvel is pretty much consistent... if you asked me which team is BETTER and has more longevity, ill say avengers... after all, you dont see a jla movie in the works, do you?