Ok, have a look at this clip from a quick bot match on the W10 version (bot match, because the matchmaking can't find anyone, surprise!)
http://xboxclips.com/Deepo/cc83c2eb-fc81-4a74-8ee9-e3f76ae0a86a
Do you see the lurching and jumping while turning the camera? That's there constantly in the MP. The clip is played with a controller, so the turning should be smooth. It's not. And this is the same whether Game DVR is on or off.
This might have been fixable if I could use RTSS to set a frame limit. But guess what: I am protected from that nasty stuff through the magic of UWP.
As said before, I was fully aware what I went into with this version. I see this as a fun tech exploration. And the single player works well enough, the stutter seems isolated to MP.