The Odyssey Millennium II 1701M2 2004 vs Odyssey Millennium II 1902M2 2005 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 — Odyssey Millennium II 1701M2 2004 at 16,0 ft versus Odyssey Millennium II 1902M2 2005 at 18,0 ft. At 14 lbs and 16 lbs respectively, both sit in a similar weight class — either should pair comfortably with most mid-size SUVs and half-ton trucks, though always confirm your specific tow rating with the motor added.
For family outings this is probably the sharpest distinction between the two. The Odyssey Millennium II 1902M2 2005 is rated for 10 passengers, while the Odyssey Millennium II 1701M2 2004 caps at 9. If you're regularly pulling extended family or a group of friends onto the water, the extra seats on the Odyssey Millennium II 1902M2 2005 could be the deciding factor.
Bottom line: Choose the Odyssey Millennium II 1902M2 2005 if your priority is putting more people on the water — it handles 10 passengers and at 18,0 ft it has the deck room to back that rating up comfortably. The Odyssey Millennium II 1701M2 2004 is the smarter pick if you want a lighter, easier-to-trailer boat rated for 9 that costs less to run day-to-day.