The 1070 is faster by about 5fps than the 980 ti.
http://www.pcgamer.com/geforce-gtx-1070-performance-preview/
It will play anything like a dream, although 144fps may be. a stretch for some games. Stuff like CSGO, BF4 should play pretty smoothly at a very high fps. Although don't expect to play stuff like BF1 at that fps.
Both of those cards should do you very well though