When two boats share the same hull type — in this case both the Sundance DX20 2012 and the Sundance F17FLX 2009 are modified vee designs with composite 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 2012 at 19,8 ft versus Sundance F17FLX 2009 at 16,8 ft. Weight tells a clearer story for trailering families: the Sundance DX20 2012 tips the scales at 1 575 lbs — 530 lbs more than the Sundance F17FLX 2009 at 1 045 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 130 hp, the Sundance DX20 2012 has a 55-hp advantage over the Sundance F17FLX 2009's 75-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 DX20 2012 carries 33 gallons versus 24 gallons in the Sundance F17FLX 2009. 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 2012 is rated for 8 passengers, while the Sundance F17FLX 2009 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 2012 could be the deciding factor.
Bottom line: Choose the Sundance DX20 2012 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 F17FLX 2009 is the smarter pick if you want a lighter, easier-to-trailer boat rated for 5 that costs less to run day-to-day.