I prefer the more compact, and unitized profile of the integral supressors. I have seen several Papoose rifles with a screw on can. In my opinion it looks like crap. Also, this will be a dedicated rig, so an external can would just be an extra piece to keep track of.
On another note, there are no aftermarket fast twist barrels made for the papoose. So at best, I would need a barrel blank + milling work to fit it to the Papoose receiver + threaded for suppressor + crowned + chambered + d&t front sight and still have to buy a can. I want an all in one solution.