I had mine CLA'ed, it occasionally had the dancing metering issue, but not enough to bother me. It seems solid now post CLA.
The main issue mine had was the frame lines were not moving and barely when it did when focusing.
That issue when it got CLA's and is now fixed and more of a mechanical issue. Rangefinder isn't too hard to adjust when needed if you feel comfortable pulling the top off.
The CV40mm I picked up cheap on photrio as a project due to hard focusing. Got it about 90% better, but attribute to occasionally binding when focusing due to the smaller body of the CLE. It doesnt seem to bind as much on my Leica M3.