I see the POD as a consumer product, and the AXE as a professional tool. Their capabilities and price points are in alignment with those categories.
But... If you are wondering about the AXE for High gain use, then this might be some education about
some of what it can do.
Axe FX II (FW12) - High Gain Showcase (28 amp models - Metal) - YouTube
But about the PODHD, last summer I watched a number of live bands playing pretty big outdoor gigs (concert in the park type deals) and one in my mind sticks out where both guitars were using POD HD500's. They were doing 80's rock and metal. Bon Jovi and Def Leppard type stuff. I was right up close, and was really amazed at how good the guitars sounded. I mean, for a cover band, the tone was great. It worked, and so if was
definitely usable. To me, 80's tone is very processed, loaded with chorus and flange and delay and "shiny" distortion, and to me this is where the POD units are most usable. Crowds are never analyzing your tone (unless it's shrill and harsh). This box did the job, and the show was great. Was it AXE like? Probably not, but the fact is it was perfectly usable and sounded great.
BUT... from what I have heard from the AXE... it is indeed a large step up. Fullness, clarity, punch, and it cuts. It to me does sound as good and alive as a real tube amp. Again, it's a professional's tool.
PS... still waiting for my purchase invite for my new XL...:ugeek