The Jeanneau DB/43 IB 2023 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 380 hp, the Jeanneau DB/43 IB 2023 has a 362-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.
For family outings this is probably the sharpest distinction between the two. The Jeanneau DB/43 IB 2023 is rated for 13 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 DB/43 IB 2023 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.
Draft is a practical consideration that many buyers underestimate until they're already at the marina. The Jeanneau Sun Fast 31 1990 draws 5,8 ft, compared to 3,1 ft for the Jeanneau DB/43 IB 2023. That 2,7-foot difference affects which anchorages you can access, which haul-out facilities will take you, and how carefully you need to read the tide tables in shallower cruising grounds.
For auxiliary power the Jeanneau DB/43 IB 2023 carries a 380-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.
Bottom line: The Jeanneau DB/43 IB 2023 at 42,9 ft offers more living space, greater range, and a more substantial offshore capability. The Jeanneau Sun Fast 31 1990 at 25,4 ft is the easier, lower-cost option — simpler to crew and a strong choice for coastal and day sailing.