At the moment in my country 1070 Ti is 20 dollars more expensive than 1070
the cheapest Palit GeForce GTX1070 DUAL 8GB DDR5 - €656.68
the cheapest MSI GeForce GTX 1070 Ti Aero 8GB GDDR5 - €678.58
the cheapest KFA2 GeForce GTX 1080 EX OC 8GB - €689.00
and the choice is obvious - 1070 Ti in overclock +800 33.5 Mh / s
(i'll try more - 35 Mh / s but 85 С and very unstable - Palit without backsplate),
and also 1070 Ti more recent model and more easily sold on market of second-hand things in the future
1070 Ti - Claymore - ETH dual mine - and go)
in general it is an eternal problem to compare the technical characteristics of products, but soon it will be easier, there will be a platform (at my signature), it will be possible to compare any card and understand what is better in 5 minute)