I am looking into getting trim tabs for my boat. I am looking at the Lenco Trim Tabs. I have a 19' Clearwater and my question is this. I'm not sure of the size to get and if the difference between the 2 sizes makes much of a difference in performance. The 9 X 12 are for boats 16' to 25', and the 12 X 12 are for boats 17' to 30'. Since my boat falls into both of these which would be the better size? I would appreciate any help I could get.