If you don't mind the ambidextrous shape and the laser sensor the Sensei is great, although if you play precision FPS at low sens I'd stick with the DA. If you do get the Sensei you should consider getting a hard pad, preferably all black, as that should make the hardware accel barely noticeable. Not sure about the new DA as I don't have one yet, but I'm not a fan of Synapse so I'm a bit wary of recommending it, but the mouse itself has been well received.
Personally I prefer the Sensei, for me the shape is slightly better, it looks damn good, the software is decent and my current playstyle allows me to use laser.
If you want precision, particularly for low sens playing, get the DA.