Yeah, GAS is pretty much a separate issue. The only thing worse than having GAS with digital is having GAS with digital AND film cameras.
I can't stop dreaming up ways to buy a new GF670 camera. I used to shoot 6 x 9 negatives long ago and the 6 x 4.5 negatives of my GA645 seem a bit tiny. The GF670 would almost get me back to where I used to be.
If you don't mind the weight, there are lots of 6x7 cameras on the used market. Check KEH for what they have in stock. Also, I've heard that Bronicas are available for cheap, too, but those are 6x6.