I am very impressed with the overall quality of Analog Warfare. The UI is lovely to look at and fairly straightforward to understand (keeping in mind I am no synth genius, so others with more experience are likely to find it very easy to use).
The sound quality is simply fantastic, right up there with many of the commercial softsynths I've come across. The built-in step sequencer for arpeggios is a great feature, and it's dead simple to use. I have not tried every one of the presets that are included with Analog Warfare, but the ones that I have tried have been very well done. The presets definitely show that Analog Warfare is capable of a very wide variety of sounds and textures.
The one thing I might wish for is a comprehensive user's guide. Analog Warfare is very powerful, and very flexible, and anything to assist the new user in learning his way around would be appreciated. I know that there are FAQ files for the older versions of Analog Warfare, but I'm not sure everything carries over to the current model. That being said, this is a free synth, and writing manuals is a time-consuming effort, so I totally understand the relative paucity of documentation.
Overall, I think Analog Warfare would be very useful for musicians working in any number of genres. You can get 70s-style bass synths out of it, acid-type leads, and really nice ambient pads as well. The arpegiator allows you to quickly put together a rhythmic bed for your song.