I look after 140 client computers, virtually all Win7. I have told my clients that if they choose to switch to Win10, they are on their own.
I remain guarded about Win10. I see absolutely no reason to run towards something with so many unknowns. Microsoft is desperate to have this intro look good. From all that I have read, they are meeting a lot of resistance.
The bottom line question is:
Is Windows 10 an updated Windows 8 with a better desktop. OR Is Windows 10 a better Windows 7.
If it is the former, they have blown it big time. If it is the latter and it really is a better Windows 7, after some time it will be a big success.
Microsoft spent a lot of money and emphasis on making Windows 10 a product that would work equally well on a Microsoft cell phone and on a Surface tablet. They have just written off many billions and are essentially closing down the $8 billion Nokia purchase – cell phones – not likely. Surface at best has about 3% of the tablet market after 2 years of trying hard. The tablet market is not growing at all. I would not be at all surprised if they close down Surface too.
So they designed Windows 10 for all these devices and the only one that it will be used on is computers. No one knows what design compromises they made to do this.
My plan is to not even consider an upgrade. Some of my clients (I hope few) will buy new computers that come with Win10. When that happens I will get a close look at it. I will only consider recommending it after a great deal of exhaustive study. Certainly, my clients will not get stampeded into a so-called "Upgrade."