Re: Stick with 8.1
The last couple of builds have placed my 930 with Win 10 pretty much on par with it on 8.1.
Did have some issues, but after doing a factory reset (so wiped but still with the latest tech preview on it) and restoring a backup (all automatic on WP) then it's been working fine since.
Admittedly it's annoying I have to wipe the user partition, but that aside I'm finding it to be pretty good.
Although not entirely confident they'll have it ship shape by December...!