Personally I think the Axe-Fx III is the most useful piece of musical equipment I have ever purchased, easily. I love my tube amps, they make me happy, but I think the Axe-Fx is without exaggeration the most useful tool a guitarist can own, full stop.
Seriously, even forgetting about how good the thing sounds, I have learned more about electric guitar gear by tweaking around in the Axe-Fx over the years than all my years of forums reading and youtube watching combined. There just is something about sitting down with a guitar and turning knobs that can teach you things no amount of reading can. And if you can conceptualize it, chances are good you can reproduce it in this thing.
Even if I didn't use the amp modeling at all, as is often the case, I'd still recommend it, absolutely. Let's forget about amp modeling for a minute and just talk about effects. I truly believe there is not a better, more comprehensive delay effect
anywhere, in any product for guitarists you can buy, than the Delay block in the Axe-Fx III. Same with Reverb. Same with EQ. Same with IR's. Same with almost every single effect in the thing with the exception of Fuzz (modelers almost categorically cannot do proper fuzz, it's just an inherent thing with the technology that necessarily removes the direct guitar->fuzz connection necessary for the effect to work right). And while I'd bet there are some other wizbang effects out there that can't be reproduced in the Axe-Fx, there honestly probably aren't many.
And let's not forget routing capabilities. About two years ago I came up with a patch layout that allows for a true W/D/D/W rig where the effects work in series (so like the delay trails get processed by the reverb block, etc) so they sound as natural as possible with zero effects weirdness or compatibility/mixing issues, while also allowing you to blend any amount of dry signal into the wet cabs and vice versa,
while also condensing that W/D/D/W signal into a simple stereo feed for Front of House routing, all with zero mix or phase issues. I don't know of anything else on the market that can come close to allowing you to just... come up with that idea and build it from nothing. Here's what the patch looks like, and a link to the thread I posted about it:
https://forum.fractalaudio.com/threads/clean-capable-w-d-w-foh-grid-routing-idea.183177/
And even aside from all that effects and rounding stuff, the amp modeling is pretty dang good too.