for not much more i'd snag the hyper 212 evo over the plus.... just make sure your case will support the height.
If i were you I would splurge on a 250gb range ssd (lots of programs require install directories to be on the same drive as the OS) its money well spent.
If you could get more specific with your intended resolution/ game library it would help. Having a single GPU is essentially headache free. SLI 770's will be more powerful out of the box, and 2-way sli is compatible with almost anything that would require that much GPU horsepower anyways...but you will be limited there because 3-way SLI can instantly become more trouble than it is worth and you'll wish you could upgrade to twin 780s instead. If you have no intention of adding on or upgrading, than for raw performance 2 4GB 770s will outperform a single 780 at high resolutions....
Keep in mind though that twin 770's of a 4GB variety will exceed price ranges for a decent 780ti.
Having a single GPU is almost always beneficial for temps, price, clutter free cases and universal compatibility.
Edited by dcyoung - 3/21/14 at 8:39am