Win 10 is reckoned to have a lighter footprint than Win 7 - don't know about Win 8.1
While we generally only see those with problems with Win10, there are those that think it's the bees knees, but MS are still working on Edge and updates for Win 10 are coming out in dribs and drabs, although there is a major update planned for November.
With updates being auto, it may be prudent to wait a while to see if MS mess up that, as they don't have the best of records when it comes to updates screwing systems as they aren't always a one size fits all.
I tried it briefly but Cortana didn't recognise I was in the UK and using the English (UK) language and then the Start button froze.
To get out of that, I had to factory reset with an OEM Recovery disk and fortunately, I had the laptop set to permanently check the DVD and USB drives before the HDD as F2 and F12 didn't work to change the boot order.
I then restored with the Win 7 external system image I had created before the upgrade - so ensure you create a full system image before upgrading.
I didn't like Edge and having to log in with a password which I had to after creating a MS account which you have to before you can activate Cortana.
As I was using IE11, I didn't feel there was any advantage doing in Win 10 to what I do in Win 7 - which isn't a lot anyway.
But as they say, YMMV