Both the Cobia Boats 19 Bay 2011 and the Cobia Boats 21 Bay SE 2011 are modified-V designs, both built in fibreglass, 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 - Cobia Boats 19 Bay 2011 at 19,6 ft versus Cobia Boats 21 Bay SE 2011 at 21,1 ft. At 1 960 lbs and 2 050 lbs respectively, both sit in a similar weight class - either should pair comfortably with most mid-size SUVs and half-ton trucks, though always confirm your specific tow rating with the motor added.
The power gap is worth calling out. Rated to 200 hp, the Cobia Boats 21 Bay SE 2011 has a 50-hp advantage over the Cobia Boats 19 Bay 2011's 150-hp ceiling - enough to notice on acceleration and at cruising speed, particularly with a full passenger load. Both carry nearly identical fuel loads - 60 gal and 60 gal - so range won't be a tiebreaker here.
Both boats are rated for 6 passengers - a good fit for a family of four or five plus guests. Comfort at capacity is another matter; the longer hull typically means more seat options and better weight distribution.
Bottom line: Performance buyers should lean toward the Cobia Boats 21 Bay SE 2011 and its 200-hp ceiling. If fuel economy and quieter running matter more than top-end speed, the Cobia Boats 19 Bay 2011 with its 150-hp rating is the more economical daily driver.