I'd rather get 1080 instead. Right now it's only about $20-ish more than 1070Ti, but has the same TDP as 1070Ti, and gives significant more hashrate (okay, probably not for memory-intensive algos like ETH...)
Availability is a big factor too and in many places the 1080 is OOS or priced ridiculously higher than the 1070ti/1070. Mining right now is really just what you can get at a price as close to MSRP as possible.