It is the version II metal version of the Bright line finder, I got it on Ebay for $200, I think at that price point, it is worth it. They come up from time to time. I think Stephen of CameraQuest is bundling the 15mm Heliar with the finder, that might be a good deal.
http://www.cameraquest.com/voigtacc.htm
The MD-2 has such nice build quality in general, it's a solid camera, feels lovely in my hands. People always ask to hold it, when I pull it out. Like all M cameras,
it just feels RIGHT in your hands. The MD-2 is like a zen rangefinder, stripped down to pure functionality. It's a great dedicated super wide setup.
To answer your questions regarding the finder:
Not much barrel distortion, the eye point seems to be straight on. The only thing that would be nice - would be a spirit level, as horizon level shots are tricky to do with super wides.
You can see in this image, I didn't quite manage to get the horizon level.
Flickr Link
I haven't been shooting too much 35mm C-41 any more, more 120 when I shoot film, I think this might be the last and only 35mm film camera that I will hold on to.
Image quality wise, I think digital has finally surpassed 35mm film, but thats another topic.
I liked the idea of a lens like the Cosina 15mm having such depth of field, that at f/8, pretty much EVERYTHING is in focus. The MD series does not need rangefinder alignment, it's not really a rangefinder I guess <grin/> it's more a point and shoot I imagine. Very easy to shoot with, when it is essentially set at f/8 and 1m scale focus. I approximate on exposure, usually around Sunny 16, and most of the time, I get the right exposure, but Kodak Portra 400 has so much latitude, it's almost idiot proof film.
Back to the viewfinder, I recommend it. It is on par with the Contax 21mm finder I used to have for my Contax G2. Comparable build quality, although slightly smaller overall size. And really well done frame lines, that seem to be perfectly aligned with the 15mm Heliar.
Thumbs up on the lens and finder, and the MD-2 of course
🙂