When two boats share the same hull type — in this case both the Gator Trax 15 in. Sides 2009 and the Gator Trax 18 x 38 2011 are flat designs with aluminum 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?
For family outings this is probably the sharpest distinction between the two. The Gator Trax 18 x 38 2011 is rated for 5 passengers, while the Gator Trax 15 in. Sides 2009 caps at 4. If you're regularly pulling extended family or a group of friends onto the water, the extra seats on the Gator Trax 18 x 38 2011 could be the deciding factor.
Bottom line: Choose the Gator Trax 18 x 38 2011 if your priority is putting more people on the water — it handles 5 passengers and at 18,0 ft it has the deck room to back that rating up comfortably. The Gator Trax 15 in. Sides 2009 is the smarter pick if you want a lighter, easier-to-trailer boat rated for 4 that costs less to run day-to-day.