Well, the pro's would be to have one gun that you could use for more than one hunting season - one trigger to get used to, one sight set-up to get used to (if you use the same set-up). I like having a ML barrel for each of my Handi's. I started with a Sidekick & bought a 22 hornet Handi to long after that. I'd just about sell the Sidekick & just rely on the Handi/Huntsmans if the Sidekick didn't have such a nice trigger (it is sweet), plus it's stainless/nickel.
The con could probably very well be getting the ML barral from Remington. Mine has been in for extra barrels since June 18th. The folks at Rem CS say it's got the barrels fitted, just waiting for the forearm. They will not ship my rifle without the forearm either (unless I cancel the order for the forearm). So, if you want it soon, tough luck, go buy a seperate gun. If you want a nice package that you can keep all packed up in a double gun locking case with both barrels, better plan on not getting it until after all the ML seasons are over this year.