Recently I bought Manga Studio under the influence of, well, some stuff I read online and that it was on sale. But truth to be told the one I got was a pretty good value anyway. And on contrary to what name suggests, you don't have to draw exclusively manga on it... The main selling point for me was the fact that it is much better for creating linework than Photoshop. And to be honest, given the low price point (I paid a total of about £50, of which £20 was the shipping from USA) I though: ah, why not treat myself? :P
I haven't really had much time to play with it until now. Although I am still jsut starting out to try all the options, so far I am pretty happy :)
Here is some catty lifedrawing of Ollie the PuddyFat.