If you buy this you get a serial key to registrate a Drum Midi Pack for the Toontrack EZ Drummer. Works with EZ Drummer version 1 and version 2 also. There are a wide range of styles that you can choose to download on the website of Toontack (you have to create a login for download). The sounds in the Midi Packs sound very realistic and it's fun in order to make recordings with it. But it would be nice if the packs could be a bit cheaper.
Good demos of the individual packs are available on the website of the manufacturer .