I’ve got it on several machines, and I have upgraded 2 of them to 8.1
From a technical standpoint, it’s ok. Some things are better than W7, others worse. The biggest problem is the user interface, which is just plain boneheaded. Once learned, however, it’s not a problem.
The real challenge of this OS is reserved for people who do not learn this stuff easily. They’re going to continue to struggle with it, regardless of the changes in W 8.1