Doodled a bit with it tonight and think it's a quite nice drum machine. The X-Y-pad introduces a new (?) feature of morphing between the three layers available for a single drum sound. Not as much as with other drum synths but imho it isn't that important for electronic music anyway - and this puppy seems to be made for that kind of stuff.
The built-in sequencer sports several (FX-) modulation options in a sequence style plus a creative life saving randomizer. In conjunction with the eight macro knobs you can achieve a lot of interesting variation across the layers and for the whole individual sound slot itself. Miss individual step shift and variable loop length though. Furthermore it seems that one can't load own samples (on the other hand it comes with 5GB content).
Well, you can't have it all. The search for the 'perfect' drum machine goes on - though Evolution is a fresh and good sounding approach thanks to its sample lib and FX. Imho far better than its pricey competitor Breaktweaker.
edit: Added some information to avoid sounding too negative. Indeed it is fun to play with Evolution, please don't get me wrong.
