The Crestliner C 2070 V 2008 is a modified-V design and the Crestliner CR 1648MT 2010 is a flat-bottom 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.
Size is the most obvious dividing line here. The Crestliner C 2070 V 2008 measures 20,0 feet overall (2008), giving it roughly 4,2 additional feet of deck space compared to the Crestliner CR 1648MT 2010 at 15,8 feet (2010). Weight tells a clearer story for trailering families: the Crestliner C 2070 V 2008 tips the scales at 1 340 lbs - 920 lbs more than the Crestliner CR 1648MT 2010 at 420 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 60 hp, the Crestliner C 2070 V 2008 has a 25-hp advantage over the Crestliner CR 1648MT 2010's 35-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 2070 V 2008 is rated for 7 passengers, while the Crestliner CR 1648MT 2010 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 2070 V 2008 could be the deciding factor.
Bottom line: Choose the Crestliner C 2070 V 2008 if your priority is putting more people on the water - it handles 7 passengers and at 20,0 ft it has the deck room to back that rating up comfortably. The Crestliner CR 1648MT 2010 is the smarter pick if you want a lighter, easier-to-trailer boat rated for 4 that costs less to run day-to-day.