My dad has had his 38 Express Cruiser since new. It's a 2006 with the 496 HO 425 motors in it, and since its inception has only been able to go about 53-56 mph (GPS). This is quite disappointing to him, so I thought I would check with you guys. This seems to be way off according to the marketing stuff. Is this possibly the way everyone else's boats run, or should we investigate it a little more?