Both the Sundance SV171 2008 and the Sundance SV19 2013 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 - Sundance SV171 2008 at 17,0 ft versus Sundance SV19 2013 at 18,5 ft. At 1 430 lbs and 1 450 lbs respectively, both sit in a similar weight class - either should pair comfortably with most mid-size SUVs and half-ton trucks, though always confirm your specific tow rating with the motor added.
The power gap is worth calling out. Rated to 150 hp, the Sundance SV19 2013 has a 60-hp advantage over the Sundance SV171 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 Sundance SV19 2013 carries 40 gallons versus 34 gallons in the Sundance SV171 2008. On a lake day that's negligible, but for coastal cruising or long reservoir runs the extra range matters.
Both boats are rated for 5 passengers - a good fit for a family of four or five plus guests. Comfort at capacity is another matter; the longer hull typically means more seat options and better weight distribution.
Bottom line: Performance buyers should lean toward the Sundance SV19 2013 and its 150-hp ceiling. If fuel economy and quieter running matter more than top-end speed, the Sundance SV171 2008 with its 90-hp rating is the more economical daily driver.