Right now I use a Bronica SQ-A system so I have a basic understanding of film in general; this is more in regards to equipment (though some more modern, automated features I am unfamiliar with).
So far the best no-frills workhorse seems to be the Nikon FE, and they are nice and cheap as well. Right now the only manual lens I have is a Pentax SMC 50mm 1.4 which I use for video work. Looking at adapters, the only ones I found involved another glass element which begs the question: are K lenses not preferable for F mount work? Back when I adapted my Pentax to a 7D, the adapter was jut a thin metal ring. The K to F mount adapters seem like they do more of a "translation" than a simple thread adaptation.
I love the split prism design of my Bronica. Is this available for 35mm SLRs? The few I have used in my life didn't have it, and I had a really hard time nailing focus quickly.
One reason the Nikon seems inviting is because I can get a 100-300mm f5.6 for ~$100. Between a 50mm and a telephoto that goes up to 300mm, they will likely be the only two lenses I need for my style of shooting.
Are there any other recommendations for a bare-bones workhorse? Something that can be used with a good bang/buck telephoto that goes to 300mm? I have heard good things about the Pentax Spotmatic, though I can't see any clear advantages or disadvantages of that over an FE. And of course, it needs to be black.