Which one is best for mining?
No doubts the 1080ti,
Seems its better to get a 1070 for mining than a 1080
1070Ti is also better than 1070.
A 1070Ti is actually better overall than a 1080.
Agreed... my 1070Ti systems earn about the same as my 1080 systems and cost less (using algo switching setup).
Maybe buying a premium 1080 card you could beat the 1070Ti but then at even more cost.