Gate Electronics are now into the airsoft HPA engine business with their rear-wired Gate Pulsar D HPA Engine with TITAN II Bluetooth that you can find at Airsoftjunkiez. According to them, the PULSAR D HPA engine for airsoft guns offers exceptional accuracy, versatility, and ease of use. With firing rates of 1-40 rounds per second and velocities of 250-650 FPS, it's great for any airsoft playstyle.
Weightless Airsoft presents the Pulsar D build which they say is the best airsoft blaster in the world with its "insane fps"... "This absolute monster of a replica DESTROYS everything in its way! Watch to see all the parts inside, and its parameters."