The Nitro 189 Sport 2005 vs Nitro 591 SC 2006 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.
On paper these two are close siblings in the size department — Nitro 189 Sport 2005 at 19,0 ft versus Nitro 591 SC 2006 at 18,0 ft. Weight tells a clearer story for trailering families: the Nitro 189 Sport 2005 tips the scales at 1 675 lbs — 1 520 lbs more than the Nitro 591 SC 2006 at 155 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.
Both boats share a closely matched power ceiling — 200 hp for the Nitro 189 Sport 2005 and 200 hp for the Nitro 591 SC 2006. Real-world performance will come down more to which motor is actually bolted on, its load at the time, and whether it's a 4-stroke or 2-stroke setup. Fuel capacity breaks the other way: the Nitro 591 SC 2006 carries 43 gallons versus 31 gallons in the Nitro 189 Sport 2005. 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 Nitro 189 Sport 2005 is rated for 6 passengers, while the Nitro 591 SC 2006 caps at 4. If you're regularly pulling extended family or a group of friends onto the water, the extra seats on the Nitro 189 Sport 2005 could be the deciding factor.
Bottom line: Choose the Nitro 189 Sport 2005 if your priority is putting more people on the water — it handles 6 passengers and at 19,0 ft it has the deck room to back that rating up comfortably. The Nitro 591 SC 2006 is the smarter pick if you want a lighter, easier-to-trailer boat rated for 4 that costs less to run day-to-day.