Uh, could that be what is generally known in the industry as advertising:lol:?
Does Micro provide an Approved Flight Manual Supplement that provides updated airspeeds? Do they require that the airspeed instrument be re-marked to reflect these new airspeeds?
If not, then they didn't apply for this in their STC. Nothing wrong with that, but what it means is that any stall speed claims are advertising, and haven't been documented to the FAA sufficiently for certification.
That doesn't mean it's not accurate information necessarily...
Consider an RSTOL converted Cessna: Robertson claims 37 knot stall speed for the 185 (compared to ~56 knots without the kit), complete with flight manual supplement providing new airspeeds for approach, and new airspeed instrument markings required. Documented, and proven. NOT advertising.
I'm sure that going through what Robertson did to achieve that certification is pretty extensive (also read as expensive), and does it really matter? Maybe not, but they've at least proven that data to the FAA and there is no doubt about those claims.
MTV