Both the Starcraft Marine 1700 I/O 2010 and the Starcraft Marine STX 186 Viper 2011 are modified-V designs, the first built in fibreglass and the second in aluminium, 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 - Starcraft Marine 1700 I/O 2010 at 16,8 ft versus Starcraft Marine STX 186 Viper 2011 at 18,0 ft. Weight tells a clearer story for trailering families: the Starcraft Marine 1700 I/O 2010 tips the scales at 1 550 lbs - 217 lbs more than the Starcraft Marine STX 186 Viper 2011 at 1 333 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 220 hp, the Starcraft Marine 1700 I/O 2010 has a 45-hp advantage over the Starcraft Marine STX 186 Viper 2011's 175-hp ceiling - enough to notice on acceleration and at cruising speed, particularly with a full passenger load. Fuel capacity breaks the other way: the Starcraft Marine STX 186 Viper 2011 carries 43 gallons versus 23 gallons in the Starcraft Marine 1700 I/O 2010. 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 Starcraft Marine 1700 I/O 2010 is rated for 8 passengers, while the Starcraft Marine STX 186 Viper 2011 caps at 6. If you're regularly pulling extended family or a group of friends onto the water, the extra seats on the Starcraft Marine 1700 I/O 2010 could be the deciding factor.
At this size, power-to-weight ratio matters more than outright horsepower. The Starcraft Marine 1700 I/O 2010 comes in at 7 lbs per hp versus 8 lbs per hp for the Starcraft Marine STX 186 Viper 2011. 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.
Bottom line: Choose the Starcraft Marine 1700 I/O 2010 if your priority is putting more people on the water - it handles 8 passengers and at 16,8 ft it has the deck room to back that rating up comfortably. The Starcraft Marine STX 186 Viper 2011 is the smarter pick if you want a lighter, easier-to-trailer boat rated for 6 that costs less to run day-to-day.