It all depends, you know. For example, 9 1/2 weeks is a very intense story about two people and their journey into bdsm, and it therefore had a profound impact on me when I read it many years ago, because of the deeply depressing ending. So, some would love it for the hot and intense scenes, and some would hate it for the - in the long run - very negative (as well as IMO just plain wrong) view of BDSM.
The Gor books - all the earliest books - are entertaining and fun sword-and-sandal stories with lots of light-hearted but hot bdsm in them. The later books are different, less plot and more arguments on the blessings of male domination over females, which suits some fine, while others get bored. They are definitly not bad, if you like a good yarn.
The Marketplace books are completely different again, more intense than the Gor books, less so than 9 1/2 week, much less plot or story as such.
As I see it, all books and fantasies have to do with either how you want real life, or how you can distinguish fantasy from reality, and that, as I see it, differs a lot from person to person. For example, to some warlike interrogation scenes are hot, because some of us do not confuse it with real life, while others of us can't help but do. Some like 'non-consensual' fantasies a lot, while not condoning rape in real life, and so on. It all varies. A good book for one person is a bad for another. Other literary facts and impressions aprt., of course.
It all depends on what you want, and maybe also what you want at any given time. I'd say if curious, give it a try. What can you loose, apart from a few hours? ;-)