I had an Aerotec 380/Yam 15hp until last year. Great package to learn with and so much fun.
A tip that I learnt is that if when at full tilt you find some water coming over the transom in to the boat through vigorous splashing, insert a block of wood about two inches thick between the transom and the two engine clamps. This will allow the engine to sit fully clamped but two inches away from the transom, therefore getting rid of any splashing.
It worked with mine
Member of S.A.B.S. (Wirral Division)
Time is precious, waste it wisely!