How do you compare the results with the V5 and the Rigid Cron?
Not quite what you asked, but I have some obliquely relevant experience you may find of interest ...
I have three 50mm Leica lenses - an uncoated f/3.5 Elmar LTM, a collapsible Summicron LTM, and a Summicron V3. I use the LTMs on a IIIf body as well as an M2 or M5 with an adapter ring, and I used them only for shooting monochrome film. Both Summicrons have been CLAed within the last year.
The uncoated Elmar is the most different for obvious reasons. When shooting into specular highlights or bright surfaces, it has a kind of ghostly "glow" that can be harnessed to great aesthetic effect. The lens is otherwise very sharp when stopped down even a little, and definitely has a kind of classic look to it.
The two 'crons are harder to compare. They both have superb rendering power and excellent contrast. The V3 is somewhat apparently sharper stopped down than the collapsible LTM 'cron but it's not really night and day. There is definitely a subjectively different look to the older lens but I couldn't tell you why, exactly.
I chose the V3 because everything I read said that the difference in optical performance between the V3, V4, and V5 was minor at best, at least for film.
The one problem I have noted is that when shooting directly into a bright light source, the LTM collapsible 'cron has some secondary reflections that cause the flare pattern to appear in the shape of the aperture blades. It's really weird. Even a CLA didn't fix that. It's not a showstopper as I rarely shoot directly into the sun - especially with a rangefinder camera, since I don't want curtain burns!