The Sea Ray Sundancer 300 2005 vs Sea Ray Sundancer 510 2002 comparison sits squarely in the category of decisions where specs alone won't tell the whole story — intended use, storage, and long-term ownership costs all factor in.
Size is the most obvious dividing line here. The Sea Ray Sundancer 510 2002 measures 51,0 feet overall (2002), giving it roughly 17,6 additional feet of deck space compared to the Sea Ray Sundancer 300 2005 at 33,4 feet (2005). Weight tells a clearer story for trailering families: the Sea Ray Sundancer 510 2002 tips the scales at 38 500 lbs — 26 010 lbs less than the Sea Ray Sundancer 300 2005 at 12 490 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 660 hp, the Sea Ray Sundancer 510 2002 has a 340-hp advantage over the Sea Ray Sundancer 300 2005's 320-hp ceiling — enough to notice on acceleration and at cruising speed, particularly with a full passenger load. Fuel capacity breaks the other way: the Sea Ray Sundancer 300 2005 carries 175 gallons versus 6 gallons in the Sea Ray Sundancer 510 2002. 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 Sea Ray Sundancer 510 2002 is rated for 15 passengers, while the Sea Ray Sundancer 300 2005 caps at 10. If you're regularly pulling extended family or a group of friends onto the water, the extra seats on the Sea Ray Sundancer 510 2002 could be the deciding factor.
Bottom line: Choose the Sea Ray Sundancer 510 2002 if your priority is putting more people on the water — it handles 15 passengers and at 51,0 ft it has the deck room to back that rating up comfortably. The Sea Ray Sundancer 300 2005 is the smarter pick if you want a lighter, easier-to-trailer boat rated for 10 that costs less to run day-to-day.