Trying to decide what gpu to buy

Hello, I am trying to decide whether to buy
R9 290X Sapphire Tri-X or
GTX970 Gigabyte
(btw, prices here are much higher GTX970 is $505 and 290X is $461 and average salary in my country is around $350 or less) but nevermind that, I just want to know what your opinions are and what gpu you think I should buy. I am gaming on 1080p 60hz monitor.

What resolution do you play games on? If its 1080, either will be fine. If its 1440p, I would go 290x for the extra 500MB of 'fast' memory compared to the GTX 970.

I am gaming on 1080p monitor (I edited my post). I am really confused watching this 3.5gb + 500mb on gtx 970. That 500mb are 'slower' than the 3.5gb? I heard that gtaV requires ~3.9gb@max on 1080p. I will also be playing crysis 3, vanishing of the ethan carter, fc4 and upcoming witcher. Do you think I'll need full 4gb? Also, watching some of the benchmarks on youtube I can see that in most videos the 970 outperforms 290x. Thanks.

I'd go 970.

Ok, let's say I am going for GTX 970. I can only go for Gigabyte or Gigabyte G1. Is G1 version worth 60 more bucks (in my country that is...)?

Can you link which models please? Is the cooler different? If not it is just clockspeeds and then that choice is up to you.