I think you know my feelings
PROS:
AMAZING unit. It is not just an amp modeler, it is a "rig-replacer". Guitar amp, guitar cab, massive effects unit, bass amp, bass cab, studio mixer console EQ, studio mixer console preamp, routing switcher, MIDI interface, USB interface, Noise reduction, DAW processing (reverb, compression, multiband compression, EQ, etc....), etc... Guys who only look at this thing as a preamp, or a reverb box or whatever is missing the point.
Great build quality. Smart design, such as a modular power supply that is easily replaced in case it gets fried.
Top of the line parts. Brown-Burr Op-Amps, TigerShark DSPs, etc... It is basically built for the highest fidelity from beginning to end. Cliff has a no compromise attitude when it comes to design. He uses the best available, not what is good for the price. You can tell this by the clear hi-fi sound.
Constant updates. The unit WILL get better over time. It is like getting a new unit all the time. Just recently he updated all the reverb models and doubled the amount. He also added console preamps. I know people make fun it of it saying "more realer!!", but just imagine if your tube amp grew a new channel every 6 months. You would be happy as shit also!
Total flexibility. Like I mentioned before, the amp block currently has 92 different controls. There are 20 or 30 different kinds of blocks. There are over 200 amp models. If you cant find your tone, it doesn't exist. It is a great opportunity to learn how sound processing works. You can also create any kind of switching you want. With the right control pedal you can basically set it up any way you want. Nothing else has the same amount of flexibility.
HUGE community. Want tips from pros who tour the world? Want tips from studio pros who know all kinds of studio tricks? Want tips from obsessed bedroom pros who have nothing else better to do? If you take the time to read through all of the resources it is kind of like getting a college degree in sound processing. SO much information out there about using this unit for tons of things.
CONS:
Because of the flexibility it is not for "set and forget" people. With the updates you tones WILL change. Embrace the change and update them. If you are that guy who is still using Windows 98 because you expect it to do what it always did and whine about having up update to run newer programs, this unit is not for you.
The sound is definitely dependent on what you run it through. Getting that huge depth punch relies on the same physics that tube amps have to follow. You need big speakers and volume. I have not found a way around this. Running through some $5 headphones is definitely going to limit you vs. some nice $800 studio monitors. Basically the Axe-FX can replace everything except your amplification system. You have to consider this system when looking at the Axe-FX.
Obviously this is not a cheap unit. However, consider what you are getting. There is a high value dollar per feature. I understand it is tough to put so much $$ into one thing. Just know that one day it WILL be replaced by something newer. You may have to lose some money to upgrade. Are you still using your rotary phone because you are afraid buying an iPhone will lose its value? Just accept that this is a part of life.