In my case the whole Windows 10 issue has pushed me to make a decision..
Moving to Linux Mint 17.3 Cinnamon from Windows 7 has been a breeze!
Performance has been great.
Ubuntu/Mint has really improved over the last year or two, since I last tried it.
Supports my L750 Toshiba laptop out of the box without installing additional drivers and all my usual apps work better than on 7 (even Skype). Around half the memory usage of 7, which means zero swap usage.
Made the switch on Sunday night and now Linux is my main platform.
Which now means I can either keep the dual boot windows 7, or format the Windows 7 partition and install Windows 7 or 10 from scratch using the Windows 7 key and use that as my 2nd platform.
I'm willing to experiment with Windows 10, but not use it day-to-day.