RE: Skymaster F18
Mike, I have a sm F-15 with a P-120 that's been turned up to 125K....making about 29 lbs of thrust. It seems perfect...especially if you are going to use tanks and/or missiles. You should be good with the 1000.
The airframe should handle the thrust....just check all of the factory glue joints and make the linkages slop-free and you'll be set.