^^
what are the prices of the cards you are looking at?
personally a good warranty gives quite some peace of mind in the unfortunate event something goes wrong. (reason why im sticking to evga for titan that is incoming soon
later down the line being able to go watercooling without voiding warranty is a good option aswell)
also what does the internet say about them? because performance wise the zotac one is top performer together with a gigabyte edition that is quite rare to buy. (or atleast around here)