I have a Kodak Stereo 35. I like it because I like kodak, but also because it is very user friendly. You almost cannot mess up because of the excellent lenses. People complain about inaccurate shutter speeds and all that, but I guess I got a good one. I have never had a bit of trouble with my camera, and I actually enjoy cutting and mounting the slides. Honestly, I could go through a lot more hassle and it would still be worth it for the results it gives.
I hear the Realists are heavy, complicated and cumbersome. I have no first hand experience. I hear the Russian jobs have light leaks. Again, I don't know. If I were to start over, I would do it the same.