Another vote for 4 cycle
I purchased a Honda 8 hp, 4 cycle Bigfoot model BF8D with the extra long shaft after some low-life(s) (certainly not sailors) stole my 15 hp 2-cycle outboard right off the back of my boat. I later found out several motors were taken that night in drydock. Anyway, I liked the 15 Mercury well enough to keep it and use it even if it was a little cold-natured when it first started. I didn't like the 2-cycle fumes and how after running for about 15 minutes at part throttle it occasionally misfired a little bit. This misfiring didn't bother me as much as my non-sailing passengers. It seems that non-sailers get very nervous when the motor on any boat hiccups a little bit. Also, my solar panel was able to keep the battery topped off, but not able to recharge it. That meant that I had to bring the battery home at least once a month to charge it, even if I didn't use the lights. Somehow dragging 50 lbs. of lead and acid over the side, to the ground and putting it in my truck detracted from the fun quotant of sailing. To me it seemed like an accident waiting for an opportunity to happen.With my insurance check in hand I set out to find a new and better motor. I made a list of the features I wanted and the features I needed and discovered for only a few dollars more I was able to get the electric start Honda instead of the electric start Mercury. Now I don't have to smell the 2-cycle fumes, the motor purrs at any throttle setting, fuel consumption should be better, the computer handles the choke, it isn't cold-natured and my battery will always be charged.What did I give up for the conveinence of this quiet, not as stinky, boat moving, battery charger? It cost me about $250 more than the 15 HP 2-cycle electric start Mercury and I lost about 1/2 knot off my top speed. Also, it was in stock and because I bought it from the local sailboat shop I was able to support one of my best resources of knowledge and experience. Besides, why not give the money to a local guy who's trying to support his family and run his own business? West Marine won't miss the money but I'm sure the local store appreciated the business.I have a 1979 O'Day 23 (about 3000# empty) with the original motor mount. I have to agree that while the motor is only about 20-25 lbs heavier than the old motor the Honda with it's 4-blade prop and better torque curve seems to be able to put much more strain on the motor mount when docking or launching. I'll be looking for a new 4-cycle motor mount too. 8 HP seems plenty for my O'Day 23 even if the boat is rated up to 15 HP.