The Beneteau Idylle 15.50 1985 vs Beneteau Swift Trawler 34S 2012 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 Beneteau Idylle 15.50 1985 measures 51,5 feet overall (1985), giving it roughly 14,9 additional feet of deck space compared to the Beneteau Swift Trawler 34S 2012 at 36,6 feet (2012). Weight tells a clearer story for trailering families: the Beneteau Idylle 15.50 1985 tips the scales at 33 069 lbs — 31 466 lbs more than the Beneteau Swift Trawler 34S 2012 at 1 603 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 425 hp, the Beneteau Swift Trawler 34S 2012 has a 340-hp advantage over the Beneteau Idylle 15.50 1985's 85-hp ceiling — enough to notice on acceleration and at cruising speed, particularly with a full passenger load. Fuel capacity breaks the other way: the Beneteau Swift Trawler 34S 2012 carries 211 gallons versus 132 gallons in the Beneteau Idylle 15.50 1985. 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 Beneteau Idylle 15.50 1985 is rated for 15 passengers, while the Beneteau Swift Trawler 34S 2012 caps at 11. If you're regularly pulling extended family or a group of friends onto the water, the extra seats on the Beneteau Idylle 15.50 1985 could be the deciding factor.
The Beneteau Idylle 15.50 1985 has a documented displacement of 33 069 lbs. Displacement data wasn't available for the other boat in this comparison.
The Beneteau Idylle 15.50 1985 uses Masthead-sloop rigging. The Beneteau Idylle 15.50 1985 has a documented auxiliary engine of 85 hp.
For extended cruising, water capacity matters: the Beneteau Idylle 15.50 1985 carries 238 gallons versus 85 gallons on the Beneteau Swift Trawler 34S 2012 — a significant advantage on longer passages where watermaker or provisioning stops aren't guaranteed.
Bottom line: The Beneteau Idylle 15.50 1985 at 51,5 ft offers more living space, greater range, and a more substantial offshore capability. The Beneteau Swift Trawler 34S 2012 at 36,6 ft is the easier, lower-cost option — simpler to crew and a strong choice for coastal and day sailing.