I've now got it on my laptop and desktop
I first upgraded the laptop when it was available which was dead simple. I then decided I wanted a clean install, which required a download of Windows 10 and then used their too to stick it on a USB stick. Again, pretty easy, I did have some issues with my mouse software, but that's a result of trying to wipe all the Vaio software to get a completely clean Win 10 install
On my desktop, it wouldn't let me "force" the upgrade because it wouldn't accept my Win 8 license key. So that meant I had to wait until yesterday afternoon for the upgrade. After it finished I had a fright where it wasn't recognising my graphics card, which meant I had a low resolution image on one of my displays.... It was luckily fixed by a quick restart
As for the experience, it's really not much better. The switch to 125% zoom has had a bigger impact on my life, I'm not sure if they've improved that system, but the difference between 8 and 10 isn't that great
It still has weird quirks where you have different menus that do the same thing. Some are basically legacy Win 7 and some are Win 8 style.
But basically it works quite nicely!