The 1080 is a no brainer at that price but I wouldn't trust it at that price! Who I their right mind would sell a 1080 for 400??
The 1070 is the best all around bang for the buck for 1920x1080 gaming, even at 144mhz (i'm doing it and it's butter). Yes, miners are driving these through the roof and buying them out and it's only gonna get worse as apparently new ether mining apps love the memory bandwidth of Pascal. If you go 1070 and can get one under $450 grab it.
Vega is not a bust since Vega for gamers isn't actually out yet (RX Vega). RX Vega may be great, but (1) you're gonna wait and (2) you'd still need to be ok with putting your faith in the hands of AMD drivers which can still be flaky and that's today in GPUs they've had out...