M2 user here. Blessed with many lenses but not either a 35 VC or a 40 Cron.
I've looked through a M3 and will agree it is a great viewfinder but the M2 offers more options for lenses. Many believe brassing and covering peeling a badge of honor, not going there other than I just had my M2 recovered as I sent it to Youxin Ye for CLA. Having the camera recovered was a no brainer considering the crud building up in the bottom of the camera bag from the covering breaking off.
Go with one of the M2s, take off the lens, open the film door, watch the shutter move at all speeds and pick the best lens/camera combo, the Cron sounds better to me.