I bought a new Smithy Granite 1324 15 years ago, and have been happy with it. If you are limited on space and you are limiting your work to hobbies and gunsmithing I think a Smithy 3 in 1 would be a good choice. The lathe performs quite well, and the mill is certainly adequate, though you are limited on travel and set-up's can be a challenge.
My Smithy machine has been reliable. I have had only 2 problems - a bad bearing in the gearbox and failed motor brushes. Both were simple fixes - and the Smithy technical service is very good.
I have machined plastics, brass, bronze, and steel, including tool steel on the machine. It took me a while to learn its capabilities, but once there, I find that any of these materials can be successfully machined to include meeting tolerance and producing a fine finish. Cutting metric and Imperial threads is also straightforward.
I have found that rigidity of the stand is crucial since the machine is quite top heavy. I bought the Smithy stand, but ended up anchoring it to the wall studs to firm it up. There was a discussion on stands for the Smithy
here.
Like others have said, you may find some used Smithy's on Craig's List, but you will want to be very careful. They are sometimes starter machines, plus the earlier models lacked protection against crashes, resulting in badly damaged components.