You'll almost certainly be perfectly fine. AMD cards generally work a lot smoother, and the open source drivers means things can be well supported all the time and it's great.

On Nvidia, in my experience, it's occasionally a hassle if you're using a bleeding edge kernel (which you won't be if you're on a "normal" distro), where something changes and breaks the proprietary Nvidia driver... And if Nvidia drops support for your graphics card in their driver you may have issues upgrading to a new kernel because the old driver won't work on the new kernel. But honestly, I wouldn't let any of this get in the way of running Linux. You have a new card, you'll probably upgrade before it's an issue, and the proprietary driver is something we all get mad about, but it mostly works well and there's a good chance you won't really notice any issues.