I can only comment on three powered cabs, PC112+, PC212+ and Catalyst 100.
I started with a Helix Floor and later added an HXStomp.
I quickly sold the PC112+ and moved up to the PC212+.
The reason was that I THOUGHT that the PC112+ was too dark. I wish I'd kept it because I later realized that I simply didn't know how to use it.
I wish that I'd kept the PC112+ because now that I know how the system works, it would have been fine, and if I only had the HXS it would have been perfect for my needs.
The PC212+ is actually overkill with the HXS. I found that the advantages of total volume, which I don't need (the PC112+ is plenty loud), and the "novelty" of the stereo possibilities, which I don't really care all that much about, are offset by the added size and weight. Stereo is nice for "ambient" sounds though.
IOW, if you have a full fat Helix and want the above-mentioned advantages of maximum volume, integration and features, and don't mind the weight, the PC212+ is great.
Otherwise, or if you only have the HXS, the PC112+ is quite sufficient.
Also, if you think of the Speaker Emulations as Speaker 1, Speaker 2 etc. and don't get all hung up on "Do the GB25, V30 etc. REALLY sound like "THE REAL DEAL", then the PC series are great for the AITR feel. Just pick the speaker that sounds best for the sound that you're going for.
The Catalyst 100 not only sounds great for AITR, but it's also MUCH cheaper, lighter, and has the advantages of being a backup if the HXS fails.
The internal amps, delay and reverb allow me to use more pre-amp FX without running into DSP issues with the single processor HXS.
With the addition of the 6 new amps in the latest X version (12 total and the old HW is updatable by FW), I have all of the amps that I need.
It's PLENTY loud (get the 2x12 version if you need more) and actually sounds GREAT for low volume (<75db) practice in my apartment.
This is due to the built-in Fletcher-Munson compensatory EQ on the .5watt setting. Even at <>60db it sounds full.
For LIVE use, going to FOH from the XLR, the "generic" sounding 1x12, 2x12 and 4x12 speaker options, with the MANY mic emulations, give me all the flexibility I need.
I went down the rabbit-hole of IRs. I have many THOUSANDS, from every major and minor player, and I no longer use them except for my RARE forays into recording, and even then, rarely. The ability (with the new FW) to disable the internal speaker emulations allows the ability to use an IR loader if I wanted to.
My PC212+ is now on Craigslist.
IOW, if I was starting over and only had the HXS, the Catalyst is the way I'd go.
All of the L6 options have MIDI, which is GREAT. It's NOT Rocket Science, and I'd be happy to answer any questions you have about using MIDI.
As to the other candidates you mentioned, the only way to tell which would be best for YOU would be to try them.
Good Luck finding a store that has all of them, and keep in mind that what they sound like in a store vs ITRW is about as accurate an evaluation method as YouTube.