Used an 8 hp Mariner 2 stroke on my 4.5 draft Southern Cross 23. Hardly ever used the full power, but it was nice to know the reserve would be there if needed, against wind and chop. Important is the position of the motor, ie. that it is deep enough and still bites when seas are choppy. BTW it still ran as new after well over 10 years, without even salting up and only home maintenance.