There are two things I really like about the Leica Summaron 35mm f2.8, and one thing I don't like.
Thing I like - Close range performance.
Once the Summaron starts focusing around four feet and closer, it starts to turn to magic. I've never been real keen on shooting people this close since I'd never really get great results. Then I tried it with this lens and was blown away. Anytime that I want to shoot a close-in portrait of someone now, this is the lens I reach for.
Thing I like - Point Lights
Not sure what it is about this lens, but when used wide open in low light, point lights take on a spectral, torch-like appearance that I happen to really like more then the traditional starburst shape.
Thing I don't like - The Goggles
The camera this lens was designed for doesn't natively support 35mm lenses. So to make this lens compatable, I need to use the version that has the big gangly goggles on it to correct the field of view in the viewfinder. They tend to make the viewfinder dimmer, and the camera bulkier. I imagine someday I will upgrade to a body that can handle 35mm lenses, and trade this lens in for a version that doesn't have the goggles attached.
The 35 lenses with the viewfinder attachment (ie "goggles", "eyes" etc) can be used on any Leica M body. It will convert the 50 mm frameline to the 35mm field of view. You can use this lens even on the latest M9 digital body.
Yup. I used them on my M6 quite a bit and actually preferred the resized 50mm frame lines over normal 35mm lines.