Looking at the Evinrude website I was suprised to note that the 150 H.0. only comes in a 20 inch shaft. The 2 new boats that I am looking at have transoms of 25 inches each (multi-species aluminum). It appears that the only option is the standard E-TEC. Any insight as to why?

Also, one of the boats takes up to a 175 H.P. slung on the back. Evinrude skipped over this size from 150 and went to 200. Again...why? Opinion?

Any advantage to the H.O. as compared to the standard?