I understand the concern about AirTabs and the claims. It is possible but unproved that there may or may not be modest fuel mileage improvement.
It is also true that there are several RV.net participants who have two decades or more of RV experience in virtually all road conditions and use AirTabs. Each of these drivers (including me) is qualified in our public courts to offer a firsthand opinion that the AirTabs do increase the stability of the RV in a major crosswind. This is termed evidence -- it does not prove the truth of the claim, but it may be considered by the trier of fact.
Even with the cost of painting to match the three colors on my coach, the AirTabs were a modest cost mod that IMHO do improve stability. One night when I was in a 40 knot crosswind, I would have gladly paid triple the cost for the benefit of the AirTabs.