Are you joking? Its a top of the pile card, with a whole lot going for it except price

. Those monitors has nothing special that it won't handle them with ease.
are
you joking?
I'm not particularly satisfied with a 780 powering just one 1080p120 monitor...
I think a single 780 Ti would be fine if trying to power a triple 1080 setup if the expectation is only for 60Hz... but not for these 144Hz ASUS monitors...
granted, it is all about expectation. I've fallen pretty hard for the motion clarity of lightboost, so I really need to try and maintain more than 100fps
but yeah, if the OP really wants to push 5760x1080 @ 100+ fps, well he's likely going to need more than a 780Ti if he also isn't willing to sacrifice on settings too much. Oh yeah, will also need a killer CPU as well, as I'm CPU limited more often than not when trying to push 120fps.
Of course a 780Ti and the G-Sync upgrade for these monitors when G-Sync arrives would probably be the best compromise (although that could get pricey)