the honda long-shaft 2HP is a great fit for the M15. i found the motor on my M15 worked great in 98% of the situations. i can think of only one time, wind/waves/tide, that i wished for a larger (more HP) and longer shafted motor. i had a fixed transom mount so i couldn't put the motor 'deeper' in the water. only when i moved forward of the cabin bulkhead did i have issue with cavitation. most times i ran the motor at about 2/3 throttle and this gave about 4.3 knts. i could run the motor about 45ish minutes before needing to refill (refill before empty as restarting is MUCH easier). the only limitation of the honda 2HP is a lack of an external fuel tank option. i carried two fuel containers on my 15 (i do the same on my 17 as my outboard on SWEET PEA is also is a internal only outboard). one was/is a one gallon and the other a 3.5 gallon. i keep the one gallon about 2/3 full and use this to fill the outboard. when the 1 gallon gets low i fill it with the 3.5 gallon. the one gallon is much easier to lift and control over the transom than a 3.5 gallon tank. i have become fairly good at filling the tank as a result of practice. challenge - the new EPA rules now mandate these over-designed flow control devices that require you to use three hands: one to hold fuel tank, second to hold spout into outboard's fuel tank, and third to trigger the flow valve. my current fuel tanks are older (about five years) and i only need to remove the stopper/vent for them to work. :: Dave Scobie :: former M15 owner :: M17 #375 - SWEET PEA - www.m17-375.webs.com :: Sage Marine - www.sagemarine.us --- On Fri, 3/4/11, Karen and Smiley <magoo252@comcast.net> wrote: Would one be better off using a shaft length of 22 inches as found on the Tohatsu 3.5 hp outboard as opposed to the 20 inch high shaft lengths of most long shaft outboards. Additionally from what I am used to on my P21 which I had driven using a 8 hp 2 stroke I felt that I never could get most of the power out of that engine to making Hull speed at about ¾ throttle. So I assumed that 2.5-3.5 hp would be just right for the M15 with 2 hp being maybe a bit shy for those BAD days when you need to boogie from a storm. Thanks What is the trick to re-fueling when you’re out in bumpy waters BTW Smiley