Curb your enthusiasm! I'm also retired. I bought an M6 simply because I thought I should own a Leica before I died. I'm using CV lenses on it because I own an R4A and also had an R3A with a suite of CV lenses and Leica lens prices are insane.
You won't see any difference in results - the difference will be entirely emotional and to do with the experience of owning and using a very nice piece of equipment. All lovely stuff, but a Voigtlander R2A would replace it very adequately.
Rolleiflex (3): E2 Planar 2.8, WA & Tele
Nikkormat FTn (2)