Lisened to it on my phone couldn't tell any difference at all course it's just a phone speaker right lol will listen later on big set up in the other room... but I would like to say as far as the helix cabinets there's a lot of options with those cabinets like being able to run two single cab blocks in parallel or even with an IR or 2 IR's also duel cab blocks with two independent cabs on each block.... there are some good YouTube videos out there on tweaking parallel cabinet setups on different paths.
I was using a lot of IR's at first I've had it for a little over a year now actually almost a year-and-a-half and if found that the cabinets in the Helix are actually really nice, sometimes you have too many options if you know what I mean, specially with IR'S and ear burnout....
the archon is my favorite amp by far on the helix it's the first I guess that I have noticed I don't even need a distortion box or anything else to use it as a lead tone it just as a nice smooth lead metal sound whatever you want to call it also the clean Channel version is very nice and sounds really really good
I've already have my 3 or 4 favourite irs so I'm not overwhelmed with options
I found that the stock cabs are good for clean or not too distorted sounds (for classic rock) but for metal they aren't tight enough for my taste.
I already tried 5150, recto, mark IV (I'm not able to make it sound good! My fault for sure), Engl and Archon fo metal and I liked the archon best, followed by the 5150.
For sololing I always use only the distortion of the amp, because I like dynamics.
For cleans I dig a lot the Hiwatt model, but I need to experiment more.