All "inexpensive" AHRS units that use soild state gyros have problems with drift in the gyro sensors. To correct for this, a calculation is done that looks at acceleration and figures out if the gyro is drifting or not. We use pitot data to do some acceleration corrections, while other AHRS units use GPS or other solutions.
We did design the EFIS to be used in fixed wing aircraft, and thus we make some assumptions about the way that a fixed wing aircaft can move in order to make the best fixed-wing EFIS that we could.
We have had a few customers install the EFIS in helicopters and they have been happy with them. Maybe we are over-estimating the errors that a helicopter could induce in the EFIS, but conceptually, the EFIS could give you incorrect attitude in a rotorcraft. The errors would be greatest doing things a plane really, really can't do, like accelerating sideways. A hover would be fine, since the pitot is not lying to us at that time- you are stopped. An autorotation would also be fine. It's backwards and sideways flight that we expect could cause problems.
First and formost what we are looking for in pitot data is the change in airspeed over time, not the absolute airspeed, and we have other sensors that are redundant to pitot, so some innaccuracy in a pitot is fine.
One unique thing about our AHRS- it is self correcting in flight. If it gets lost at some point, it will correct itself once you are near level and not doing anything too strange.
