A number of people work successfully with the GTX 970, among them Bill Gehrke. There are no known compatibility issues AFAIK.
The GTX 970 will be around 30-40% faster than the 760, but the main advantages are the lower power consumption, HDMI 2.0 support and the reduced chance of running out of VRAM.
You recommend installing the latest Nvidia.com drivers or run the original MSI drivers?
The nVidia drivers, currently version 344.75 WHQL.