Geoff Berliner told me I am NUTS to use the 6.5x9cm backs. 9x9cm is what makes this camera a handholdable special dream to use. High Speed lenses were a requirement back in the Atomic Age. LOL Geoff told me he saw a 9x9cm Rolleiflex, at the Rollei Museum in Germany. Myself I'd rather use the Makis.
How many Makiflexes do you see in Geoff's basement treasure trove?
He told me he has over 1500 large format lenses. WOW.
And 1500 Speed Graphics! I asked him if that was enough? LOL
Actually I love my 6.5x9cm backs too, they are the real deal. But Makina Backs are finicky to use, the design is archaic and very unusual. But they can be made to work well and consistently too. If it's an important shot for me, I will shoot it with multiple different emulsions, to give myself a choice in the darkroom printing. And in case one of the backs starts acting up. Really I should get all of mine CLA'ed on the long term. All olde Plaubel stuff is similar to Leica quality in terms of finish and the way they handle, but in the larger format IMO.