Which graphic card

I have the R9 290 from MSI its good but I did have to change thermal paste as the old paste dries fast.

The 970 is better but you get what you pay for.

pay more and get slightly better results
 
What you pay for any hardware component can vary, greatly, from week to week depending on the release of new hardware and demand for current hardware. A card that was 250.00 last week might be only 200.00 this week, so buying the most expensive component isn't always a good indicator that you're getting the most for your investment.