is this the be-all-end-all digital distortion plugin? NO! but it can do a lot once you get the graphical interface... it actually has a few awesome presets you could never make yourself like the fuzzy stuff or cold biased tubes settings. I use this pretty frequently to make rough and gritty distortions or fuzzy octave effects, especially across a broad frequency spectrum. Its great for getting those Geoff Emerrick "revolution" kinda sounds on a DI guitar track or for making run of the mill drum samples into something hideous and industrial. Want to get an early Al Jourgenson vocal sound? Look no further. The mix control is a nice feature too, though FL has a blend knob built into each insert slot... all in all this is a very versatile distortion VST with a cool, informative interface that takes a scientific approach that I really enjoy.
Whenever I need distortion, this is the plugin I go to. I think it (along with other great Image Line plugins) is available on Image Line's website, and it's definitely worth it.