I am purchasing a 4 hp evinrude/johnson for my 8 foot trinka fiberglass dinghy. I am finding lots of these engines with the weedless prop. This prop is at a slight angle from horizonal. How does it work? Would it be an avantage or disavantage on a dinghy? Thanks for any information. I did searches on google and this site without much of an explanation as to how this thing works and how it affects the power etc.