Keith
The best camera is one that still works!
Olympus OM viewfinder blows away the nikon fm and the pentax spotmatic. It's actually the biggest 35mm viewfinder I've ever looked through, and it's plenty bright. Haven't used a contax SLR so can't compare with that. But I'll be surprised if it's much bigger than an OM finder.
And that's the thing that blows me away about the Oly finder ... not just the brightness but the size of it. My FM3A wasn't far behind the OM finder in brightness but it looked very small by comparison.