I have a gtx 980, and it's a pretty damn great card (which you'd expect). Considering I only use a 1080p monitor and only play moderately intensive games, it's pretty much overkill for what I do, but it's worth it imo. However, 2x 970's in SLI should be faster than a single 980, so if you're looking for a better overall performance to price ratio, dual 970's should be better.
EDIT: I hope you enjoy your 980 and it fits your needs.