I have an original (not composite) Roo with a Ram 500X (also 12 lb thrust). I believe that it weighs about 13 lbs dry. It is fairly light because it has ultracoated wings and fins.

It flies great with this combination, and in my opinion is a perfect turbine trainer. We consistently measure with a radar gun 140-150 mph during low passes at full power, which is just about what you want for a turbine trainer.