When two boats share the same hull type — in this case both the Sea Ray 540 Sundancer 2010 and the Sea Ray 580 Sedan Bridge 2012 are semi displacement 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?

Size is the most obvious dividing line here. The Sea Ray 580 Sedan Bridge 2012 measures 58,6 feet overall (2012), giving it roughly 3,8 additional feet of deck space compared to the Sea Ray 540 Sundancer 2010 at 54,8 feet (2010). Weight tells a clearer story for trailering families: the Sea Ray 580 Sedan Bridge 2012 tips the scales at 515 lbs — 510 lbs less than the Sea Ray 540 Sundancer 2010 at 5 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 861 hp, the Sea Ray 580 Sedan Bridge 2012 has a 287-hp advantage over the Sea Ray 540 Sundancer 2010's 574-hp ceiling — enough to notice on acceleration and at cruising speed, particularly with a full passenger load. Both carry nearly identical fuel loads — 6 gal and 7 gal — so range won't be a tiebreaker here.