This is the best mixing application there is. PERIOD! I have been mixing records for a while, mostly drum N' base and break beats, and love the fact that I can use my laptop in the mix. I use an imic along with the headphones jack and send the signal in to my mixer on the line channels. Then when I can use my 60 gigs of digital music to mix with my vinyl. This also gives me the mids on my mixer and the ability to use the fader in a more natural style.

Dj18k is also great for practicing, or just seeing if two tracks will work together. Sometime you have to use sound flower to get the signal to go where you want, but now I can mix records late at night with out bothering the neighbors. Keyboard shortcuts are easy to learn, and I suggest using them.