When two boats share the same hull type — in this case both the Grady-White Canyon 366 2009 and the Grady-White Marlin 300 2013 are modified vee designs with fiberglass construction — the buying decision usually comes down to a handful of practical questions: how many people are you putting on the water, how far do you trailer, and what does your tow vehicle weigh?

The power gap is worth calling out. Rated to 1 050 hp, the Grady-White Canyon 366 2009 has a 350-hp advantage over the Grady-White Marlin 300 2013's 700-hp ceiling — enough to notice on acceleration and at cruising speed, particularly with a full passenger load. Fuel capacity breaks the other way: the Grady-White Canyon 366 2009 carries 42 gallons versus 3 gallons in the Grady-White Marlin 300 2013. On a lake day that's negligible, but for coastal cruising or long reservoir runs the extra range matters.

For family outings this is probably the sharpest distinction between the two. The Grady-White Canyon 366 2009 is rated for 11 passengers, while the Grady-White Marlin 300 2013 caps at 9. If you're regularly pulling extended family or a group of friends onto the water, the extra seats on the Grady-White Canyon 366 2009 could be the deciding factor.