Both the Crestliner Backwater 1860 SC 2011 and the Crestliner C 1860 VS 2006 are modified-V designs, both built in aluminium, so 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 - Crestliner Backwater 1860 SC 2011 at 18,4 ft versus Crestliner C 1860 VS 2006 at 18,0 ft. Weight tells a clearer story for trailering families: the Crestliner Backwater 1860 SC 2011 tips the scales at 880 lbs - 310 lbs more than the Crestliner C 1860 VS 2006 at 570 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 power gap is worth calling out. Rated to 115 hp, the Crestliner Backwater 1860 SC 2011 has a 65-hp advantage over the Crestliner C 1860 VS 2006's 50-hp ceiling - enough to notice on acceleration and at cruising speed, particularly with a full passenger load.
For family outings this is probably the sharpest distinction between the two. The Crestliner C 1860 VS 2006 is rated for 6 passengers, while the Crestliner Backwater 1860 SC 2011 caps at 4. If you're regularly pulling extended family or a group of friends onto the water, the extra seats on the Crestliner C 1860 VS 2006 could be the deciding factor.
Bottom line: Choose the Crestliner C 1860 VS 2006 if your priority is putting more people on the water - it handles 6 passengers and at 18,0 ft it has the deck room to back that rating up comfortably. The Crestliner Backwater 1860 SC 2011 is the smarter pick if you want a lighter, easier-to-trailer boat rated for 4 that costs less to run day-to-day.