If the 35 Summicron is half as good as my 35/2.8 Elmarit-R, you'll have one heck of a wide angle prime. Sharp across the entire frame, even deep into the corners, with beautiful color rendition. To give you an idea, I have a capture sharpening action for my 5D2 raw files that works really well with images taken with my Canon lenses. The Leica is so sharp, that after running the capture sharpening action, I have to back off the opacity of the sharpening layer all the way down to 20%...I can probably get away without using any capture sharpening at all, the files are that crisp. Granted, its only 2.8 as opposed to F/2, but its a great little lens in a very small package. You can pick one of these up for about $275 USD, the Summicron f/2 for about $600 USD, give or take. The Elmarit is a great lower-cost alternative to the Summicron, but if you need to have F/2, then it won't do you much good.
I use the Eg-S focusing screen in my 5D2, with a Happypagehk focus-confirm adapter. Matter of fact, all of my wide angle primes are older MF lenses from Leica, Olympus, and Zeiss. Wouldn't leave home without them. Here are a couple test pics taken with the Leica Elmarit-R 35 on my 5D2 (sorry about the tilted ones...was in a rush and didn't use a tripod):
Leica 35/2.8 Elmarit-R, F/8
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Leica 35/2.8 Elmarit-R, F/16 | Byte size: ZERO | Content warning: NOT AN IMAGE |
Leica 35/2.8 Elmarit-R, F/2.8 (focus point on the top lip of planter)
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