I'm not convinced that the MPX is worth double the cost of a Scorpion, but they sure are nice. Very intuituve "AR" style controls, plus a very welcome Bolt Release for the Right--hand Trigger Finger make it very smooth to operate. The Scorpion controls are pretty good as well, just not quite as nice as the MPX. But what really sets the MPX apart from the EVO3 is the operating system and its effect on perceived recoil. The piston-driven operation of the MPX produces a very soft perceived recoil coupled with the increased operator safety provided by the locked breach. Compared to the raw blow-back operation of the Scorpion, the MPX wins hands down for controllability. Does that make it worth double the cost of the Scorpion? Not necessarily, but it does make the MPX a worthy successor to my MP5 in terms of handling, controllability and shooter comfort. A bold comparison perhaps, but entirely fitting I believe.