I was maintaining three fabric planes that were sitting side-by-side on our ramp. One had brand new (2 month old) Stewart on the wings & tail and 30 year old dope on the fuselage, one had 25 year old polyfiber, and one had 15 year old SuperFlight. Enter one heavy hail storm. All three aircraft were insured and were write offs in the eyes of the insurance companies. Upon examination, the Superflight, Dope, and Polyfiber all showed substantial ringworm damage. The Stewart was still plastic enough that it didn't ringworm so much. However, the Stewart finish had numerous tears and separations through the weave of the fabric that had to be patched. None of the other systems failed in that manor. The other planes only needed some dobbing with dope and/or rejuvenator to make airworthy again. However, the crux of it was that all three planes were easily patched up and flying again within a week or so, and all three have since had at least the wings recovered. This probably doesn't pertain a lot towards the long term wear on the Stewart system, but based on my observation, I don't think it protects the fabric quite as well as the other systems. Despite the minor differences in the level of damage to these planes and the fact that I really like the traditional nitrate and butyrate dopes, I will likely use Stewart system in the future just to reduce my toxic exposures.