1. Failing at zone focussing a 25-20mm lens is really hard to do, even the best AF can be wrong btw. The Hassy Superwide allows you to mount a ground glass back but then you can't shoot. The normal finder is a classic viewfinder sans distance calculating or rangefinder help and it costs several hundred to thousands dollar more.
Have you ever tried a wide lens missfocused in medium format? Do you believe that just because its lens is wider it will work the same way as wide lenses in 35mm?
Well, I have the 35mm f/3.5 Sekor on my Mamiya 645 and it is not hard to focus as you say. When I do focus incorrectly in close ranges it is quite obvious even at f/8.
As for the AF, I do not own a medium format AF camera with such a wide lens, but my Nikon F100 with the ultra wides of mine has never misfocused.
2.Regarding the build quality sorry guys but if you buy an old Folder severals things can be off not only the lens but also the focussing mechanism, the bellows, the standart, etc...
The point is that there are quite many of a way higher quality than that of the LC-A 120.
3.The lens of the LC-A well the examples of pictures I've seen so far range from crappy to good some seem to have heavy vignetting I guess wide open+ flash and some have no vignetting at all. There are also plenty of people who like vignetting.
You have to admit though that it is a very expensive vignetting to like it that much.
4. The price well it is expensive, but it is also the only super wide angle camera in this price class all others are either much more expensive or not 6x6 but 6x4.5. If you like square you can get the Fuji/Voigtländer or a Mamiya 6 both are much much much more expensive.
I am amazed of how much some are willing to pay for something of low quality just because of being super wide. It could be of course that I am wrong and $500 are too much for this just for me.
7. Nikos have tried the camera yet or are you just assuming because the AE of the LCA might just be good or even as good as the GF670, on the build quality you are probably right allthough at the beginning there were plenty of QC issues with the 670 and if anything the LCA should be compared with th GF670W. Also the lens of the LCA is much wider than the GF670W's. So basically you are right they shouldn't be compared the only camera that directly compares to the LCA is the Hasselbald SWC which is no doubt much better but lacks an exposure system and costs several thousand $ more.
Don't expect matrix or spot metering on that camera. It will have the same filthy light meter of the classic LC-A with a new silicon cell. What do you really expect from a meter like that, that cannot be considered at least center weighted.
If all that matters to you is the field of view of your camera, and all you will ever need is that wideness of the LC-A, and you don't care of the quality of your photos, and you always let the camera decide on the exposure, then that camera might be more than enough for you.
But in that case, a 35mm tinny point and shoot is far better than a larger 120 (just 12 exposures per film) point and shoot camera (o.k. have zone focusing as a plus).