It's obviously a comprimise whenever two extremes such as shotgun barrels & rifle barrels on the came action are considered.

On a 470 for example - you need a lot more wood in the butt (especially in butt/surface area) while in a well-balanced, weight-between-the-hands game gun (shotgun) that big stock puts too much weight rearward... and the barrels feel "whippy." There a whole host of other things "ideally" wrong with dynamics of each gun's specific handling characteristics in this scenario.

Now, practically speaking - I think there is a lot of "cool" factor (not sure about how much more convenient it than just reaching for another gun) to opening the oak & leather case, pulling out a set of 12's and swapping them for the 470's while the trackers load your buff, kudu or just taking a break on a slow morning!

There are thousands of dove over there and although I say I want to - I never take the time to shoot them.

If you've got the money, get the shotgun barrels too.

Just don't expect the shotgun barrels to feel like a 20-gauge Dixon round-body... because that just can't be done in the rifle / shotgun combo.