Matching a inflatable non rigid Achilles 156SB 2010 against a inflatable rigid Achilles SU-18 2008 means you're likely deciding between two genuinely different on-water experiences. Hull type shapes everything from ride quality and fuel burn to dock handling and resale trajectory.
On paper these two are close siblings in the size department — Achilles 156SB 2010 at 15,5 ft versus Achilles SU-18 2008 at 18,0 ft. Weight tells a clearer story for trailering families: the Achilles 156SB 2010 tips the scales at 185 lbs — 141 lbs more than the Achilles SU-18 2008 at 44 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.
The Achilles SU-18 2008 tops out at 90 hp. Engine specs for the Achilles 156SB 2010 aren't listed — confirm with a dealer before selecting an outboard.
For family outings this is probably the sharpest distinction between the two. The Achilles 156SB 2010 is rated for 12 passengers, while the Achilles SU-18 2008 caps at 11. If you're regularly pulling extended family or a group of friends onto the water, the extra seats on the Achilles 156SB 2010 could be the deciding factor.
Bottom line: Choose the Achilles 156SB 2010 if your priority is putting more people on the water — it handles 12 passengers and at 15,5 ft it has the deck room to back that rating up comfortably. The Achilles SU-18 2008 is the smarter pick if you want a lighter, easier-to-trailer boat rated for 11 that costs less to run day-to-day.