I have had some very good experiences with EVGA cards/warranties. EVGA use to sell lifetime warranties. I returned a card for repair that had a lifetime warranty and the replacement is still going strong. I tend to hold on to video cards for a long time. I have three GTX 970's. Two I bought from craigslist. One had major issues and could not mine at all. Turns out, it was still under warranty and I got a replacement from EVGA in 3 days! I have bought extended warranties on all my EVGA video cards and have used those warranties three times with great results. I highly recommend EVGA.
They have the best service I have experienced so far.
I have also had good experience with MSI, Gigabyte, and ZOTAC.
PNY was good at first but then they decided not to honor my receipt from Amazon anymore by the 3rd time I sent in an RMA.