I'd love to have a 6P for the amazing camera and all the other specs are outstanding as well! Wish I had waited for this phone instead of getting the Nexus 6 on Project Fi.
The 5X is nice, but too small for me and hasn't been received to the same fanfare as the 6P. That said, it would also make for a great comparison with the OP2.
I've never had a Nexus phone and have always wanted one. I've heard nothing but good things about them. I'll take the 5x or 6p, whichever one I can possibly get!
My wife is a long time iPhone user and she is getting more frustrated with using it. She has expressed interest in learning more about android and she thinks she wants one. The Nexus 5x would be perfect in size for her, and it's a great phone.