I have accumulated a lot of CV lenseswhich I use on my Bessa R and also on my M2. The R does feel a bit plasticky but works really well, especially the meter, and for the price who cares about a bit of plastic!
The lenses that I have are the 15mm, 21mm, 25mm, 35mm Ultron and Nokton, 50mm Nokton, 75mm and the 90mm. Yes, I know that I need to thin them out, but which ones!? Most used are the 35mm Nokton and the 75mm Heliar, but hey, they are all great lenses, especially for the price.