I am torn between getting a Canon 50mm f/1.4 or a Voigtlander Nokton Aspherical 50mm f/1.5 for my Bessa R.
Both seem to have overall good reputations and I could pick up either for under $300, something that may be hard for other fast lenses in LTM.
The Canon 50/1.4 is faster by 14%. The VC is a much newer lens, possibilty taking advantage of design improvements over the last 40 years. I probably can get the VC in slightly better cosmetic condition or without any traces of oil on the aperature.