i currently own a merc 115 efi 4 stroke, i am very pleased with the performance, but i have only had it for 1 season.
i also own a honda 10hp 4 stroke. i have owned this beast for a long time. i used it on a tracker topper 14. it was used all summerr to fish out of and then it became my duck boat thru the winter. it never let me down even on the coldest N.E. mornings.
not to mention it spent three days on the bottom of my lake after a big storm sank my first boat. it started right up after i drained the crank and changed the plugs.
so i guess the bottom line would be the honda is a great motor, but the cost is also great.
my short expeirience with the merc is right on track with the honda.
hope this info helps.
GregD