The Crestliner C 2070 VS 2006 is a modified-V design and the Crestliner Suncast 2185 2008 is a pontoon design, so you're likely deciding between two noticeably 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 - Crestliner C 2070 VS 2006 at 20,0 ft versus Crestliner Suncast 2185 2008 at 20,0 ft. Weight tells a clearer story for trailering families: the Crestliner Suncast 2185 2008 tips the scales at 1 900 lbs - 1 100 lbs less than the Crestliner C 2070 VS 2006 at 800 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 C 2070 VS 2006 has a 55-hp advantage over the Crestliner Suncast 2185 2008's 60-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 Suncast 2185 2008 is rated for 9 passengers, while the Crestliner C 2070 VS 2006 caps at 8. If you're regularly pulling extended family or a group of friends onto the water, the extra seats on the Crestliner Suncast 2185 2008 could be the deciding factor.
Bottom line: Choose the Crestliner Suncast 2185 2008 if your priority is putting more people on the water - it handles 9 passengers and at 20,0 ft it has the deck room to back that rating up comfortably. The Crestliner C 2070 VS 2006 is the smarter pick if you want a lighter, easier-to-trailer boat rated for 8 that costs less to run day-to-day.