I have an M8 with the 35mm summicron and 75 summicron, and am looking for a wider lens that is not very expensive, since I don't shoot very wide most of the time. I have read great things about the CV15, which is equivalent to a 21mm on the M8. Eventually I hope to make the move to an M9 some day (maybe in a year or two), so I think about how lenses would perform on both cameras before buying them.
I am leaning a bit toward the CV21mm, because I think the CV15mm would be a bit too wide for me on the M9, and 28mm would probably be wide enough for me on the M8 (although I wouldn't mind just a bit wider, like a 24mm). Both CVs are now rangefinder-coupled and come in the M-mount; the CV15mm is more expensive. I don't know much about the performance of the CV21on the M8. Part of me says to get the CV15 because I can always sell it later if I don't like how it would eventually perform on a M9, and I would slightly prefer a 21mm over a 28mm on my M8.
Anyone have any comments on how these lenses compare in optical and other qualities on the M8?
Thanks very much,