For years, I used a Mamiya RB67 for my studio portraiture work. They always worked, a lot of options with lenses, screens, finders, etc. Though heavy, I've used them hand held when my Mamiya 645 bellied up at a wedding. It and my C330f saved the day. About 10 years ago, I parted ways with it, along with most of my film equipment.
In the past couple of years, I've started shooting film again, and I've accumulated a number of different cameras, including a Cambo 4x5, Super Graphic, Mamiya C330s, and a Mamiya 645 Pro TL. Only missing was a 6x7. I wanted a RB67 Pro SD. A local dealer had one, and I almost pulled the trigger, until he showed me a mint RZ67 Pro that had a WL finder and a 90mm f3.5 lens. The attraction of the electronic shutter, and single cocking/film advance lever was just too enticing. Now I'm a RZ67 owner, and I found an AE finder last night on eBay. Can't wait to get it into the rotation.
The same dealer also had a mint condition 6x7 "23" Graphic back for my Super Graphic, and 3 BNIB Riteway 4x5 holders.