It's safe to say that Superior Drummer really does set the industry standard in digital drum production. An exceptional product that stands far above the rest, Superior Drummer 2.0 is the complete drum studio for those who want to record high quality music without access to a full drum kit with high grade microphones and a drum room. Toontrack sells the drum studio software for $349,and many will tell you (and I agree) that this is hands down one of the first investments a musician should take in building your setup. It's got an excellent-sounding sample engine, and the room sounds are phenomenally realistic. It includes lots and lots of GBs of awesome drum sounds, so you should be able to cover any sound or style you're looking for. It also features presets by Neil Dorfsman, who has produced music for major artists including Sting, Bruce Springsteen, Dire Straits, Kiss, Joss Stone, Genesis, John Mayer, and Chris Cornell. I have asked many trained sound engineers to listen to tracks with Superior Drummer used as the digital drums, and not one of them guessed it was software. Who says a drum machine can't have soul? Really impressive stuff.
Get more info on the Toontrack website.