Lonewolf
It's much simpler than that, actually. The biggest drawback of the Handi is to buy the barrel the receiver has to be sent back to H&R, have the barrel fitted and return to you.
From then on it takes about 30 sec to change barrels.
Simple remove the forearm screw, remove the forearm, and open the barrel as if you were putting a shell in. Hang on the to barrel cause it will fall off in your hands. Reverse the process to install new barrel and you are done!
If they ever come out with barrels that do not have to be "fitted" they will not keep up with demand, for sure.