The ultimate, best made, best designed and nicest to use, the M3.
Everything after (except the M5) was less in every way.
The fact the M3 was so great, means even the lesser M's are wonderful.
The CL and CLE are not reliable. (my experiences).
My M2 purchased never used in 71, requiring a full CLR, to work.
I love the clarity, the clean viewfinder frames, non flare viewfinder.
Warning! My M2 is first batch and no spares, the button rewind, shutters.
My M6TTL is really a good camera, with wrong way shutter dial, terrible 50mm frame and a counter that hates to re-zero.
Yet compared to the plastic, throw away of other makes, it is superb.
The Canons are good BUT screw mount except for those ultra fast 50mm lenses. It is not an M-mount.
All Leica M cameras are special.