We have tried both the Acme 515 and 525 both with similar results. The wake is small but very firm. Even at 28 off the wake is really not very good. We have taken all extra weight out, skiing with no back seat and 1/4 tank of fuel. We have tried no observers, 2 observers, weight in the nose. Nothing seems to work. Any other suggestions, the next step may be a for sale sign.