You know I tend to separate out live rig from recording rig as I'm such a fan of the eleven rack (and plugin options) in the studio and I don't play out much. When you just want to play electric guitar though, there's something about playing through an amp that's totally different - call it feel. You're not looking for a great stereo image, you're looking primarily for tone and touch sensativity. I own a Fender Mustang IV v1 and was excited about this amp when I bought it for these reasons:
1.) a lightweight 2x12 with everything in the box - a small footswitch is all you need and you can achieve a lot of sounds, no pedals required.
2.) a true stereo amp with powerful full range Celestion speakers - so you can plug in your elevenrack, your line6 HD500 whatever into the stereo effect loop in the back and just run through the power section. No other combo amp has this to my knowledge.
I think my Mustang IV sounds good but not great. It lacks the real guitar amp sound that I'm hearing/feeling in the Boss Katana and therein lies the rub.
So I'm attracted to the Katana head and the Jet City cab - the cab is using non-full range guitar speakers and is inexpensive and relatively lightweight. The benefit for going with the head is, I can buy other heads down the road if I want and just use the same cab.
RANT WARNING
Here's the thing that REALLY bugs the crap out of me about the Katana. Only 4 presets. What the heck were they thinking? 4 sounds per song might be good enough but in a live situation I want to be able to switch between banks of sounds for each song WITHOUT having to bring a flippin' laptop to the gig. You can program swap 55 different, beautiful sounding Boss Effects into the 4 presets inside the amp but NOT without a laptop. This to me is a major drawback. What I would've preferred is bluetooth, a footswitch or similar that allows full access to all the parameters in a portable solution and for banks of presets so you can store your sounds in the amp!! Someone wrote an android app to control the Katana but honestly, I don't want to fck around with a hacked solution. Roland/Boss should've done this. If they had made a panel like on the mustang where you could flip though every parameter on a small screen and edit right on the amp itself, this would've been great. So why didn't they? Because they figure this is too much information for guitarists to handle. They've obviously never been to this forum!