Still running 7, but I wouldn't buy a copy today if building a new rig. I would get a copy of 10 and figure out how to best tweak it to suit my needs.
I probably would have gone that route if:
a. Setting it up one time would definitely stick. Meaning no checking after every damn update to see if they have reset to spying on you.
b. I believed that they have actually admitted to, and put in place controls to stop all of their spying. I very much doubt they have actually admitted to all the crap they have in place, even after their latest round of saying what they are actually collecting.
edit: For the record, I do have Win10 Pro on one PC (along side a dual boot of Ubuntu 16.04) as a test bed.