Enjoying my two Galax 970 EX OC's.
They run well, minimal issues thus far - I was getting a lot of flickering on light sources in Titanfall, but forcing Alternate Frame Render method two for game in control panel and it's gone.
They clock to 1474 on the core, though not played much with the memory.
Just need to get them under water - top card hitting over 80C depending on title/load!
Edit: have not noticed any degradation in image quality, but I have made sure I have the nvidia cards to force full colour RGB - in some cases (display connection) nVidia can resort to limited - God alone knows why!