Been reading about hulls etc and how they can affect MPG (GPH). We are looking for a boat for cruising the ICW but don't want one that will only hit 10 knots max. Would like something a little faster for the few occasions we may cross the bay (or just outrun a storm). Like the looks of the 34' Silverton and 35' Sea Ray. Are there boats like this that will get us 2 MPG ( or 5GPH) when running slow (7-8 knots). We know it will suck fuel when opened up but mainly interested on economy on long slow runs like on the ICW.