GTX 770 4GB vs R9 280X-Help with upgrading video card

I Was hoping to get some opinions or some first hand experience from people who have these cards. I have $200 GC to Newegg, so I'll be looking to purchase there.

If anyone could shed some light on which would be better for longevity/gaming, and if it would make sense to over pay (they are marked up more than a hundred because of litecoin miners) for the 280X or go with a GTX 770 4GB. I like the fact that the 280X has 384 bit bandwidth compared to the 256 bit 770 and I was wondering if that would be a serious bottleneck for future games? Or do i stop this madness, pay a little more and go to the next tier? As you can see i really dont know where to draw the line.