Yes, Bill.
As long as we adhere to 110-12 (the catch all code!) then barrels are just fine.
Put them strategically into a corner, and strategically fold all conductors into the box, crossing them as little as possible.
Doesn't take anymore time than cramming them in and sorting the mess out during trim-out.
Keep in mind, that before 99 code, 300-14 was taken to mean 6" inches of free conductor (outside of the box?!?) to the AHJ in this area. 99 NEC clarified that much to our relief.
We developed good rough-in habits doing it this way though, now that we can use much shorter wire! I still do a maticulous job with my boxes, makes trim-out a snap!
