I have had my SSout once this year. It was last weekend (May 23). Put on two flights, # 29 and 30. I am using a Saito .91. I have had a constant problem of the cowl mounting holes getting "keyholed" by vibration. I came up with an idea, tried it, and it works!! I took some fuel line and carefully cut off very thin slices - like 1/16 inch, or one millimeter, to make soft washers out of. I then put Futaba servo mounting flat washers on the cowl screws, with the fuel line under, and turned them in tight enough that the fuel line washers begin to bulge out. Problem solved! The silicone pushing against the cowl keeps it steady and prevents it from vibrating.