When two boats share the same hull type — in this case both the Larson 1850 LX 2010 and the Larson SEi 180 LX I/O 2007 are modified vee designs with fiberglass construction — the buying decision usually comes down to a handful of practical questions: how many people are you putting on the water, how far do you trailer, and what does your tow vehicle weigh?
On paper these two are close siblings in the size department — Larson 1850 LX 2010 at 18,8 ft versus Larson SEi 180 LX I/O 2007 at 17,0 ft. At 2 375 lbs and 2 365 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.
The power gap is worth calling out. Rated to 225 hp, the Larson SEi 180 LX I/O 2007 has a 35-hp advantage over the Larson 1850 LX 2010's 190-hp ceiling — enough to notice on acceleration and at cruising speed, particularly with a full passenger load. Both carry nearly identical fuel loads — 23 gal and 23 gal — so range won't be a tiebreaker here.
For family outings this is probably the sharpest distinction between the two. The Larson SEi 180 LX I/O 2007 is rated for 8 passengers, while the Larson 1850 LX 2010 caps at 7. If you're regularly pulling extended family or a group of friends onto the water, the extra seats on the Larson SEi 180 LX I/O 2007 could be the deciding factor.
Bottom line: Choose the Larson SEi 180 LX I/O 2007 if your priority is putting more people on the water — it handles 8 passengers and at 17,0 ft it has the deck room to back that rating up comfortably. The Larson 1850 LX 2010 is the smarter pick if you want a lighter, easier-to-trailer boat rated for 7 that costs less to run day-to-day.