I started playing him with the superior gasket, then switched to the one where you don’t lose pressure while shooting (mostly so I could do some challenges). And if you plan to shoot the crank gun all the way it’s much better - you can shoot without side effects, and after all, if you don’t lose the buff, a single crank is keeping the stack at 5. Handy for hordes.
I like to use the “career weapons” when possible, for fashion statements, but I think the best ranged weapon to complement the crank gun is the handgun: fast and far-away shots, which is what the crank gun is lacking.
I thought about using the flamer, mostly because you can - while maintaining some anti-special capability - but its best feature (horde clear) seems to be a bit redundant with the crank gun. Why do you use it? Which difficulty?
Leading shots’s awesome to improve armor damage with the ultimate.