I've had many a Shocker and actually, I am getting a Droid Saturday.
I'm really lazy so here's this quote from YDNA. About the Shocker design of course.
Originally Posted by ZDSPB
The other benefit to this type of spool design is the energy efficient design that it utilizes. When examining the amount of energy that is wasted per shot, it is found that the placement of the dump chamber as close as possible to the breech of the marker is optimal for energy consumption, which would mean the mechanism to move the bolt can then be placed further away (bolt sleeve in this case). This makes sense from a pneumatics standpoint, and is the exact type of design used in the Shocker. Other markers, such as the Matrix, use a design where the moving mechanism is closest to the breech, and the dump chamber is located behind it. In this type of design the air firing the ball must be shunted through the middle of the moving mechanism before it reaches the ball, and energy is lost during this activity. In the Shocker, however, the path of airflow is much shorter and more pronounced, allowing for a noticeably less energy used per shot. This is, in my opinion, what makes a Shocker one of the premier spool valve operating platforms.
This is viewed during experimentation by observing the amount of time it takes pressure to release. In a Shocker this time is generally 1-2 milliseconds, whereas is 2-4 in some other markers.