i was thinking about a voigtlander vc I or II. any thoughts on those?
I use and highly recommend the VC II. When I received mine I was stunned at how tiny it was--the size has to be seen to be believed. I can and do leave this meter mounted full time on my M2, and can still easily close my standard Leica never-ready case, which to me was a huge and unexpected bonus. The LED's are much brighter than I expected so they are easy to see in bright sun, it's easy and very fast to use, accurate, and did I mention it's TINY?
I also have a Sekonic L-208 which I used to use on this M2. I always thought the Sekonic was fairly small (although it's MUCH larger than the VC II), but it did have some some drawbacks--it looked totally butt-ugly on the camera, and of course had to be removed every time I wanted to close the case. As a result, I gave up using it mounted, and just carried it as a pocket meter, which worked ok, but was also something else to carry around and mess with. The tiny little VC II looks like part of the original M camera when mounted. I love it. If I get another non-metered M some day, I'm definitely also buying a VC-xx for it at the same time. Once you've tried one of these, you'll never look back.