Which first? Assassin's Creed or Mass Effect?

I need to choose one to play first. Can't play them at the same time as I'll loose interest in one of 'em. I know they're the complete opposite, that's why I'm asking.

They both have gorgeous visuals. I just dunno which one will be more entertaining...

Mass Effect :D

I own both and ive played Mass Effect way more since getting them both, it has a much better story, better characters, better atmosphere, etc..

I think its probably good to get both games, as i like them both, but Mass Effect is one of those games that is just so amazing and a must own for everyone IMO :D

i just got assassins creed and i really enjoy it. mass effect looks good to but i haven't yet played it.

Mass Effect looks like the better game, judging by your opinions.

Also, I got both, I just didn't know which one to play first.

I guess, like some suggested, I'll play AC, since it's shorter and "more repetitive" as said by some of you, if I do get tired of it, I would then switch to ME and when I clear ME I'd get back to AC.

Thanks for the opinions, well valued :D

Happy Holidays to you all.