Both the Scout 170 Costa 2008 and the Scout 187 Sportfish 2009 are modified-V designs, both built in fibreglass, so 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?

On paper these two are close siblings in the size department - Scout 170 Costa 2008 at 16,0 ft versus Scout 187 Sportfish 2009 at 18,0 ft. Weight tells a clearer story for trailering families: the Scout 187 Sportfish 2009 tips the scales at 1 510 lbs - 530 lbs less than the Scout 170 Costa 2008 at 980 lbs. That difference is meaningful if you're working within a half-ton or three-quarter-ton truck's tow rating, especially once you factor in a motor, gear, and fuel.

The power gap is worth calling out. Rated to 150 hp, the Scout 187 Sportfish 2009 has a 60-hp advantage over the Scout 170 Costa 2008's 90-hp ceiling - enough to notice on acceleration and at cruising speed, particularly with a full passenger load. Fuel capacity breaks the other way: the Scout 187 Sportfish 2009 carries 45 gallons versus 30 gallons in the Scout 170 Costa 2008. 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 Scout 187 Sportfish 2009 is rated for 6 passengers, while the Scout 170 Costa 2008 caps at 5. If you're regularly pulling extended family or a group of friends onto the water, the extra seats on the Scout 187 Sportfish 2009 could be the deciding factor.

At this size, power-to-weight ratio matters more than outright horsepower. The Scout 187 Sportfish 2009 comes in at 10 lbs per hp versus 11 lbs per hp for the Scout 170 Costa 2008. The lower the ratio the more explosive the acceleration - meaningful on a short RIB where bursts of speed, quick planing, and agility in surf or tight waterways define the experience.