When two boats share the same hull type — in this case both the Sundance DX20 2013 and the Sundance SV171 2012 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?
On paper these two are close siblings in the size department — Sundance DX20 2013 at 19,8 ft versus Sundance SV171 2012 at 17,1 ft. Weight tells a clearer story for trailering families: the Sundance DX20 2013 tips the scales at 1 575 lbs — 1 450 lbs more than the Sundance SV171 2012 at 125 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.
Both boats share a closely matched power ceiling — 130 hp for the Sundance DX20 2013 and 115 hp for the Sundance SV171 2012. Real-world performance will come down more to which motor is actually bolted on, its load at the time, and whether it's a 4-stroke or 2-stroke setup. Fuel capacity breaks the other way: the Sundance SV171 2012 carries 34 gallons versus 24 gallons in the Sundance DX20 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 Sundance DX20 2013 is rated for 8 passengers, while the Sundance SV171 2012 caps at 5. If you're regularly pulling extended family or a group of friends onto the water, the extra seats on the Sundance DX20 2013 could be the deciding factor.
Bottom line: Choose the Sundance DX20 2013 if your priority is putting more people on the water — it handles 8 passengers and at 19,8 ft it has the deck room to back that rating up comfortably. The Sundance SV171 2012 is the smarter pick if you want a lighter, easier-to-trailer boat rated for 5 that costs less to run day-to-day.