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I have my Q now. But before I even had it, I ordered some C mount lenses.
The lens on the left is a 25/1.4, available from a variety of chinese sellers. It's very cheaply built.
The lens on the right is a real beauty though. A little big for the Q, but with a great precision feel to the adjustments. Plus it's 5.7-34.2mm f/1.0, so the specs are pretty nice too. The crappy part is that it's CS mount, and for some reason I can't guess at no one makes an adapter. I've had a look though it by holding it up to the camera, coverage is close to good enough, certainly good enough for 1:1 format, depending on zoom it might be good enough for 4:3. Resolution seems semi-decent even at f/1.0, though this is very hard to judge without an adapter.
If I'm lucky I'll manage to modify one of my adapters for it, once they arrive.