Reference cards are all the same underneath, you are buying for the brand and 3 years warranty.

Still consider "OK" for me as you said, other cheaper brands also 2.8k, and asus's ref at 3.2k...
http://www.lowyat.net/2015/06/asus-geforce...ced-at-rm-3199/

p/s: You said non-ref? 2.9k? What's the exact model name? AFAIK, giga only have 2 980ti at the moment, one is ref, another is g1, which retails at 3.4k (someone above got one at 3.1k, and that is his discount price for getting bundle already). 2.9k seems too fishy to me.