I'll just say this:
When the Axe Fx III and the first revisions of the ARES modeling algorithms (yes, ARES is the new unified FW architecture but at the same time it's the new generation of modeling algorithms, just as diferent as Quantum was to G3, G2 etc...) first came into the scene, people compared it to both the II and AX8 on Quantum 10 (that was the rev that "incorporated some of the ARES modeling algorithms") and the differences where so minimum that people were reluctant to even think on selling their II's to upgrade to the newest boy in the family. Then it came the ARES 2.00 port to the Axe FX II and people were raving about how much alive and punchier it felt compared to Quantum (The AX8 didn't got any of the 1.00 and 2.00 revs of the ARES ports, that's the revs we're discussing here).
As I see, it was after Ares 5.00 where the Axe FX III really took off and left both the Axe Fx II and the AX8 behind...
Don't get me wrong, the AX8 still sounds great but... I've just played for about 3 hours with the Axe Fx III with FW 12.03 and then switched to the AX8. Man... you can really feel the difference, OK I get that maybe more than one will not find so much difference in an A/B blind comparison between two recordings, BUT just under the fingertips I felt something was REALLY missing from the experience. The upcoming FM3 promises a seamless switching experience between both units and if there's a possibility (as small as it can be) for the AX8 (and to an extent the Axe Fx II) to narrow the gap, then I'm 100% rooting for it. If not, that's OK too, just based on my experience with both units as of today, I may be considering a FM3 once it hits the streets, but in order to get that, sadly the AX8 will have to go unless something good happens to my pocket and I can justify keeping it as a backup, LOL.