I bought Artillery about a month ago, and I'm still learning a lot about it, and figuring out how I want to use it in my workflow, but so far I can give the following feedback:
-Artillery is very special, because it allows audio FX to be punched in and out with keys on your MIDI keyboard/controller. There are not many VSTs that can do this, and Artillery makes it easy. This is especially useful with Ableton Live, because I can create a separate MIDI track, and record clips of myself playing my Audio FX in a spontaneous and improvised way. It's a lot of fun, and sounds good! There aren't many VSTs that can accept MIDI control from a separate track in Live.
-The Looper and Step Looper FX are fantastic... I'm still learning mastering them, but they sound great. I like that I can even loop backwards.
-It's designed intelligently, fairly easy to make changes, and there are interesting options for internal modulation sources that I have only begun to scratch the surface.
-You can only use the FX that are built into Artillery... it would be nice if I could load in an audio effect from Ableton Live, or Reaktor - for instance.
-The simple and diffusion delay FX work on some kind of sampled audio buffer, and the buffer keeps a certain amount of audio in it's buffer, even after you use the effect, so it plays old audio when you are triggering it on a new section... the end result is that it sounds horrible, and I find those FX are nearly useless. I emailed their tech support about it, but no one responded. I get the sense that development for this product may have ceased - it's several years old.
-I have looked through maybe 5 or 6 Global Presets, and I found them to sound very bad, or need a lot of tweaking. I don't understand why they have some of the settings that they do... for example, their mix settings were all turned down very low, so you couldn't hear any of the FX when they were triggered... but that's no big deal - I ended up making my own template anyways.
-The EQ's in Artillery don't sounds that great compared to the stock EQ3 modules in Ableton Live. I did some tweaking and I made them sound better, but I think those could be improved.
It's a great product. There simply aren't many alternatives if you want MIDI-key-controlled punch-in of audio FX. The fact that this VST has been around for many years and is still for sale testifies to it's strength and usefulness, I think. It's already a key element of my current workflow, and it's only becoming more important as I become more fluent with it.