The 770 is a fantastic card if, like you said, you would stretch your budget. It's pretty much a 680 overclocked rebadge, so it will go head-to-head with the 280x, and thanks to the mining bullcrap, the 770 does it for much cheaper.
== Gigabyte Windforce for $329 usd
== Gigabyte Windforce for $439 usd
$110 dollars more. Get real, Newegg.
AMD cards at the current state don't make sense over nVidia if you are getting them to game with. Only the 290 and 290x (even at $100 over MSRP) are sort-of worth buying, but just because they are the new fastest Hawaii GPU. So if you aren't looking to get into the upper-high-end, go nVidia.
EDIT: Holy crap, that site has the Royal Queen 280x for 288 euros, and 770s tend to be priced quite higher than that. If you're going to use Dinokomp, that might just be the best deal on their site. I stand corrected.Edited by hathornd - 1/10/14 at 10:59am