I bought a used GS645 in the 90s. Had Fuji USA replace the bad bellows and a CLA. It worked reliably until it was stolen. I bought a replacement and had Camera Wiz do the same job to it. I still have it and it works fine, if not heavily used. I'll go with Qualls on the Pearl III. They have gotten a bit pricy, but probably no more than a Mamiya 6 folder. I have a Pearl IV, and IMO it is the smallest, best folder 645 format camera ever made, but it comes with a premium price these days. I've owned two Mamiya 6 folders, and I've never liked either one. The optics seem a bit hazy, and they are heavy as a brick in your pocket. So, best optics and imaging, GS645; smallest, coolest, an nearly perfect, Pearl IV. Compromise: Pearl III. I do not care for a 6x6cm format, but if I was looking for one now, I'd top my list with an Agfa Super Silette or its Ansco branded equivalent, but pricy. I have a GA645Zi, and it is very nice, but it is not really an alternative when looking for a MF folder. It's much larger, and it's auto functions and electronics strip away all of the tactile feel and thought process of doing it yourself. (But it does do all of that very well indeed.)