AFAIK the GGR chip requires the MAP sensor to be connected. The limit of the standard injectors is about 270bhp, to set the boost level properly you will need a rolling road session where air/fuel ratio and injector dutycycle can be monitored.

The stuff about disconnecting the MAP sensor for the Superchip is bull, the Superchip calibration doesn't use the MAP sensor so it makes no difference if the sensor is connected or not.