My first post here, hi. I like my Contax G2, but it has a skimpy viewfinder. What if I used a 40mm finder (Voigtlander?) for a better view with the 45mm lens? Anybody try this? Other finder suggestions for this lens?

Welcome. You may want to check that the diopter adjustment (knurled wheel to the right of the finder) is set properly for your vision before buying a supplemental finder.

I use the Voigtlander 40mm finder with my Fuji GW690 and 90mm lens. I bought it for my 40mm rangefinder lenses, but it's a very close match in coverage for the 690, and the view is higher magnification (about 85-90% lifesize with the Voigtlander), and much brighter and clearer than the Fuji finder. I've briefly handled a G2, but can't make a valid viewfinder comparison for you.

Lee