lots and lots of lawyers? I fail to understand why putting two things in one box warrants a patent, but that's just the way I am.
They look ok, depending on how much power you drive through them, there may be an issue with integrated amp/motor combinations. Lots of servo drive applications have nearly no power going through them on an average basis.
If you are buying them used, I would check to see if there are any gotchas, such as software you must buy. Also, do they meet your power requirements, can you get the connectors you need. There are all sorts of reasons why such a motor may be on the surplus market, some of which are no good for you.