You aren't going to OC? If you aren't why would you go for such expensive mobos? And why go for the unlocked version? Mobos at those price points don't differ much.
See what features you want or need and chose accordingly. Any of those boards are great. I also like my MSI Z170A Gaming M5.
But if you aren't going to overclock it's not worth to go to a K CPU and or to go for a Z mobo