The Jeanneau Prestige 680S 2019 vs Jeanneau Sun Fast 31 1990 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.

The power gap is worth calling out. Rated to 900 hp, the Jeanneau Prestige 680S 2019 has a 882-hp advantage over the Jeanneau Sun Fast 31 1990's 18-hp ceiling — enough to notice on acceleration and at cruising speed, particularly with a full passenger load. Fuel capacity breaks the other way: the Jeanneau Prestige 680S 2019 carries 924 gallons versus 13 gallons in the Jeanneau Sun Fast 31 1990. 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 Jeanneau Prestige 680S 2019 is rated for 21 passengers, while the Jeanneau Sun Fast 31 1990 caps at 7. If you're regularly pulling extended family or a group of friends onto the water, the extra seats on the Jeanneau Prestige 680S 2019 could be the deciding factor.

The Jeanneau Sun Fast 31 1990 has a documented displacement of 6 834 lbs. Displacement data wasn't available for the other boat in this comparison.

Both boats draw a similar depth — 5,1 ft and 5,8 ft respectively. Marina access and anchorage options should be broadly equivalent between the two.

For auxiliary power the Jeanneau Prestige 680S 2019 carries a 900-hp engine against 18 hp on the Jeanneau Sun Fast 31 1990. Motoring range and ability to punch through a foul current or enter a tight marina under power will favour the more powerful installation.

For extended cruising, water capacity matters: the Jeanneau Prestige 680S 2019 carries 54 gallons versus 26 gallons on the Jeanneau Sun Fast 31 1990 — a significant advantage on longer passages where watermaker or provisioning stops aren't guaranteed.