Wow. What else can I say? I have never found any amp emulator, hardware or software, that was able to produce a satisfactory clean guitar tone. That is, until I bought my copy of Amplitube. This is an amazing plugin. Playing my Fender Toronado DE-9000, I have been able to get an astonishing variety of tones. Bright ones, dark ones, evil heavy metal and grunge tones, crystal-clean, jazz-type ones, and spot-on 60's garage. If you've ever used a guitar amp before, it will be very simple to dial in a good tone. The CPU usage is quite low (10% on my P4 2.4 1gb ram, Sonar 3.1.1). Stability is very high, no funky weirdness at any time. Not even a hiccup. However you will want to mute your guitar while changing patches, or you'll get a "pop".
I have played tube amps for years, and I know that no plugin can touch the tone or responsiveness of real amps. Nevertheless, there are several reasons for guitar players who record music on computers to seriously check this thing out. First off, the sound quality is superb. I don't know how they did it, but they did. The touch is not like a real amp, but it comes pretty close. It is very playable, and quite satisfying. Even though the sound doesn't quite match up to "the real thing", consider that you will never have to replace any tubes. Not only that, but for a measly $300 or so you can get a virtual roomful of classic amps to play around with (and it takes way less space). Another nice feature is that you can easily put any instrument through it for subtle coloring or perhaps complete destruction.
It comes with a good assortment of presets, which are designed to demonstrate the breadth of the sounds you can get from this thing. It even has some bass presets. Most guitar players like to see a few examples before adjusting their own settings, so I think there are enough presets for most people. Additionally, the IK website has a user preset section that's pretty well stocked. The main benefit I've derived from the presets is figuring out how to best use the post eq section.
As for tech support, never tried it. The documentation is excellent, covering each feature in detail. There is even a training video on the website. I do agree with the other reviewers in that challenge-response authentication is not ideal. It works, but it's an added pain. While we're on the subject of things I don't like, add in that the delay is not tempo-syncable. That's the worst problem I could find so far, and it's no big deal because chances are you've got at least three tempo-syncable delay plugins installed right now.
All in all, this is the perfect plugin for computer-oriented guitar players. You'll have a nice assortment of tones to use for recording or even just playing (imagine that). I got a copy of T-Racks for free (their special limited time 2-for-1 deal), so I'd have to say it was a tremendous value for the money. I would have bought it anyway, though, because it just sounds so damn good.
Amps, preamps, stompboxes, speaker cabinets, mics, effects... all modeled on famous vintage hardwares used by reknowed guitarists and bassists.
Extract from the text : "AmpliTube 3 contains over 160 pieces of gear including models from the most sought-after vintage collections and modern day workhorses. You'll get 51 individual stompboxes and effects, 31 amplifier preamp & power sections, 46 speaker cabinet models, 15 high end stage and studio mics, and 17 post amp rack effects. Plus, with the AmpliTube 3 open architecture, you can add more packages as you need them."
Why is KVR sending notification that Amplitude has a "new version" (v3.1.4) as of today (2015-04-02). Version 3.1.4 was released on 2014-07-17. According to the IKM website, v3.1.4 is the latest version.
Just to inform you, there is a free new update for AmpliTube in your the User Area -> My Products section (https://www.ikmultimedia.com/userarea/) of your IK Multimedia account. Make sure to download this and check out the new AmpliTube 4.6 version's general reliability improvements and integration for iRig Stomp I/O.