Depends. If you are not in a rush wait a bit for Threshold 2. This is probably November (been pushed back once already).

That said, I upgraded on two machines and have a third Windows 10 machine and I like it. Edwin has had some issues but part of that is that there are so many possible configurations for a Windows box they have to have things pretty open ended. Apple has an advantage here since they have a very finite set of machines this runs on.

When you reserved a copy (through the small icon on the system tray) did it say it was ready for you?