I had 8 of these and had to RMA most of them due to attempts at repasting and also just GPU death in general; I have one 290X Tri-X Sapphire still holding strong with the middle fan broken (cheap Tri-X fans eventually melt the center pin) but yeah it's a loss-leader it basically voids the other 5 1070s on the same rig in terms of profitability.
JCE CNv8 you can get 900 on with 1120/1420
For some reason, I've never had any luck with temps with repastes on reference type of coolers.
With the aftermarket coolers, I usually could achieve a better temperature if the card is a few years old but with the reference models, repasting doesn't do anything.
I am assuming that they use a better-longer-durable quality of thermal paste than the aftermarket manufacteurs or that simply the reference way of cooling is bad in general and without upgrading to an aftermarket cooler, the temps will always run high.