I intend to put in some radiant heat shields on the exhaust and to cover the actuator with reflective foil tape where possible. Hopefully the actuator is spec'ed well above the actual power needed for the job to help offset the temp concerns. If these things can help my RV provide better climb performance without sacrificing top end speed significantly, I am going to try em....
The positive results posted by Dan and Ken around their own designs and tests and the testing Allan has done looks promising. I have no idea if this actuator will live in the environment for a 1000+ hrs or not but I will let you know how it goes.
In the event of poor service life, Allan's setup could easily be converted to some other home brew actuator that could be designed from the start for high temps.