Should I go two 760s or 1 780?

Solution
Stick with a single strong card. Many games don't like or use SLI at all. In the future when SLI improves and receives more support, add another 780 and your all good :)


Haha, I love your picture. Also, should I wait for maxwell or jump on the 780?
 
Maxwell is not coming out this year. No ETA and it might even get delayed. Especially if both companies keep fighting over the high end segment of the market.

If you want you could wait out towards the end of the year, as new cards R9 290 and GTX 780 Ti are coming out soon. Prices could further adjust (by going lower) in reaction to the release, and of course you can catch discounts for Black Friday/Christmas.
 


As far as ive seen i havent seen any issues with SLI and i run with 2 760s