Here’s a comprehensive comparison of current GPUs when used with blender by the german site HardwareLuxx:
Just click it you don’t need to know German to understand the listing.
I replaced my Vega 64 with two RTX 2070s based on that listing and can confirm the timings stated there. Based on that I assume that the results for 1070 / ti are also correct and then the 2070 is a clear winner.
Edit: P.S.: This test is about a OC Card. I have that exact model and a ASUS RTX 2070 Turbo (The blower style card) They perform very similar. The Turbo in classroom is 4 seconds slower than the OC one. I hope this helps with your decision.