I have been wrestling with what to do lately. I have the 8x10 but also want something smaller because I'm sure there will be days I feel like shooting, but don't feel like shooting 8x10. I toyed with the idea of a 35mm Bessa-r but a few people here got me thinking of the quality jump in MF, so I started combing ebay for MF kits. I settled on a used "645 Super" kit and it's mint, and it was a good price. Any quirks I should know about these? It's my first mf system 
I've also broken the news to my other half and She seems to have taken it well, phew!
I've attached the ebay description and a few pics of it.
"Immaculate condition Mamiya 645 super Kit. Bought recently.Need to sell as received Hasselblad kit as gift. Original owner ran only 8-9 rolls of film.
Camera body, 80mm f/2.8 N lens (with rubber hood), AE Prism- ALL in almost perfect condition (9+/10). 120 Back (with insert) has barely detectable mark from glue when slide holder came loose. (See Photos). Grade the back as 9/10 for that reason. Will also include cable release adapter and strap.Also original boxes for back and Camera body, and manuals for camera, AE prism. Also battery.
Everything works perfectly, and looks beautiful !"

I've also broken the news to my other half and She seems to have taken it well, phew!
I've attached the ebay description and a few pics of it.
"Immaculate condition Mamiya 645 super Kit. Bought recently.Need to sell as received Hasselblad kit as gift. Original owner ran only 8-9 rolls of film.
Camera body, 80mm f/2.8 N lens (with rubber hood), AE Prism- ALL in almost perfect condition (9+/10). 120 Back (with insert) has barely detectable mark from glue when slide holder came loose. (See Photos). Grade the back as 9/10 for that reason. Will also include cable release adapter and strap.Also original boxes for back and Camera body, and manuals for camera, AE prism. Also battery.
Everything works perfectly, and looks beautiful !"