It combines sample playing extremely well with numerous types of drum synthesis, which can be mixed and matched and tweaked freely.
To date it has 13 different synths and 4 different samplers. This is a lot to explore, yet there are enough presets or LM4 kits to import so that you can get started immediately, without having to "get technical".
There are other goodies also inc auto flam, alternate, roll and sequence.
An attractive feature is the animated interface so that from one single screen you can see everything that it going on, no matter how complex the kit, an essential to my mind.
I don't own Battery or Attack, but DR-008 appears to combine the best of both for around the same money, another good point.
Angus Hewlett, the author, is committed to developing the product with promises of more features, synths etc. So far he has backed this up with the free Synare synth module, which is some proof of this committment.
17 months later: Still using it. Drum machine of choice!
20 months later: Now got low cost Slicy and Fill-In Drummer Plugs. Just keeps getting better.