The Sea Ray 510 Sundancer 2013 vs Sea Ray SLX 400 2023 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 510 Sundancer 2013 measures 50,8 feet overall (2013), giving it roughly 11,2 additional feet of deck space compared to the Sea Ray SLX 400 2023 at 39,6 feet (2023). Weight tells a clearer story for trailering families: the Sea Ray SLX 400 2023 tips the scales at 20 794 lbs — 20 360 lbs less than the Sea Ray 510 Sundancer 2013 at 434 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 543 hp, the Sea Ray 510 Sundancer 2013 has a 163-hp advantage over the Sea Ray SLX 400 2023's 380-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 SLX 400 2023 carries 25 gallons versus 4 gallons in the Sea Ray 510 Sundancer 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 Sea Ray 510 Sundancer 2013 is rated for 15 passengers, while the Sea Ray SLX 400 2023 caps at 12. If you're regularly pulling extended family or a group of friends onto the water, the extra seats on the Sea Ray 510 Sundancer 2013 could be the deciding factor.