I have shot both SLRs and range finders, and I think in the dark, with fast lenses, range finders are easier to focus. However, I'm not the the Bessas are the right choice for this, as their range finder effective base length is a little shorter than Leica or Zeiss Ikon. This means they are just a little less accurate. For most lenses, it makes no difference, but you may find a difference if you use very fast, longer lenses like a 50mm f/1.4, f/1.2 or faster. For a fast 35mm, it's probably going to be OK though.
Don't get me wrong, I've owned a Bessa, they are great cameras.
I would suggest however a used Zeiss Ikon or if you don't mind not having a meter, a Leica M2, M3, or M4. If you're shooting negative film, I think a meter is fairly optional.
The Bessa R3A with the 40mm f/1.4 is considered a very nice range finder kit too.