Well I currently own a 970 which is great, but the drivers are not that good on Windows 10 for quite some time now. Driver reinstall every time Windows starts, crashes other annoying stuff. It is getting better now, but still some issues.
I have had AMD before and never had a issue with drivers (5870).
Don't get me wrong. I still think my purchase was a good one, but I bought it when the card was just out. If you can buy a 390 for around the same money and benchmarks show that it runs the games you play well then go for the 390.
I however would probably wait for the new graphics cards. I like to buy my cards when it is still hot out the oven.