Very good for a unit which is ten years old. It is very cheap (about $300-$400) but difficult to find. The sound it makes is amazing if you compare it to many DigiTechs, Rolands or TCs, of course it can't get near an Eventide, but you can easily get ten A2s for one eventide. There is no disturbing noise coming from it due to a very good noise gate (even with the noise gate off, there is almost no audible noise). The preamp section is a bit weak, because it doesn't have very many parameters, but it sounds much better than any POD or J-Station, even sounds better than my DigiTech 2120!! It doesn't sound like a tube amp, of course (for that I have a Rocktron Piranha, because it's better than the Triaxis) but it has amazingly good digiteal distortion (not just clipping diodes or overdirven Transistors, it really seems to add the frequencies to your signal) The chosuses are very good, and so are the other effects, you just have to get the hang of putting them together right, no good turning Flange, Chorus and Reverb up completely on one preset and hoping it sounds good. Has a very good parametric EQ-section and never sounds mushy (except if you want it to, e.g. turn up basses full and everthing else down) REMEMBER: Most of the sound in this unit comes from the programmer! You want a specific Sound: THINKING about what effects you need to get it, dialing in the effects chain, and tweaking it to perfection is YOUR job, not the unit's!
Can't really tell, it's never made any problems in the ten years of it's life, but I have heard that the backlight of the LCD-screen tends to get weak with time, mine is still perfect. It's only been in Studio-Use, so I don't know how it turns out to react to road use - it's not very sturdily built, plastic front and so on... We'll see... I give it an eight, because I think it might be problematical in live situations, if you're not careful with it.
My setup: Ibanez Universe UV7BK, an old one with old pickups, MUCH better than the new ones, a Rocktron Piranha, MUCH better than the Triaxis, especially considering the price you pay, a MESA/BOOGIE Strategy 500 Stereo Poweramp (if you get a Poweramp, get a MESA, there's nothing like it!) and four MESA/BOOGIE Thiele Road Ready Speakers with the Proline version of the EVM12L in them. I play mostly heavy metal (In Flames, Arch Enemy...) and NU-Metal (Papa Roach, Korn...) It suits my stile perfectly, I don't know how it reacts to blues and jazz, probably it has to vomit ;-) I wish it had a pitch shifter, but on the other hand, I use it after the preamp, and a pitcher should go before the preamp, so I couldn't use it anyway. I have been playing for 5 years now, and have owned many different Preamps and Effects thingies (including three DigiTechs, ART SGX2000, KORG AX300s), but the Setup (Piranha + A2) is unbeatable, especially for the price paid (Eventides may be better for studio use, but I don't think You really hear the difference in live applications. What's more, it's INSPIRING!!!