Ok thanks guyīs, donīt know how I got that 350 hp idea in my head.
No, the reason really is just to explain to others that the engine is derated (well or actually power limited due to gearbox) and its easier to explain using the horsepower figures.
I for example have a 206B with the C20 engine, which is 400 hp and since I usually fly at lower altitudes in cold climate it really makes no difference for me to have the C20B engine or the straight C20. Canīt use the horsepower anyway.
Thanks again.