I understand that there is a Hoya range which claims tougher easy-to-clean coarings but I haven't tried them and I forget their range name. The Bronica SQ camera takes photographs on 120 and 220 roll-film, 135 cartridge-loaded film and Polaroid Land pack film, using exclusive film-backs for each film type. Both have great glass quality but I found that Heliopan rings bind too much for me and those Hoyas are just too tough to keep clean and I've got fairly severe cleaning marks and what looks like coating abrasion after two years use.
Bronica sq a pro#
My own experience with Heliopan and Hoyas Pro 1 range is less good. Unfortunately they aren't the cheapest but they are often available on eBay used and you have a fairly common size, which might well be OK since they are pretty tough. They have mostly solid brass mounts and great glass.
My own choice in amongst that lot would be B+W. Otherwise get the usually a bit cheaper standard mount. After 3 failed attempts (Pentacon Six with a bad shutter, Bronica SQ with a dead shutter, Bronica SQ-B with dead Electronics) I finally found a Bronica SQ-A in like-new condition for a decent price and bought it. If you ahave or are going to get a 50mm S lens then it might be worth getting a slim version. At the time he was shooting mainly a Bronica SQ-Ai, and his shots blew me away, I knew I had to get a 6×6 SLR. You can either use circular or linear with the Bronica. The "quality names amongst polarisers are B+W, Heliopan and some ranges within the Hoya brand.