The Windows 7 and Windows 8 releases were frustrating if you were a Wacom tablet user. After using Windows 10 for two weeks on 5 different PCs with my Wacom tablets, I can summarize the experience as this:
With regard to using a Wacom tablet with Windows 10
- Nothing got worse
- Nothing got better
So, if you've been using Windows 7 or 8, at least from the Wacom pen perspective there isn't anything to fear from upgrading. My upgrades were very fast, each machine took about 30 minutes to go from starting the upgrade to being able to log in.