The Ninja Smart XL Pro Air Oven or DT251 is the most capable and, predictably, the most costly of the five Ninja Foodi Ovens. It contains an in-built thermometer to help you cook a prime rib or any form of protein to perfection.

The Ninja Foodi DT251, by the way, is a convection oven with a bigger fan and exhaust system than any of the flip-up ovens.

With it, this model of Ninja oven cooks more evenly than its smaller brothers, reducing the need to flip your dish halfway through.

It also has a larger cooking capacity, allowing it to roast an entire chicken, a 12-pound turkey, and a large amount of beef. Taking that into account, it's a significant bonus for its other nine functions: air roasting, air frying, baking, dehydrating, toast, pizza, bagel, broil, and reheat.

It's a fantastic countertop oven with a lot to offer.

The Ninja DT251 comes with an air fry basket, two wire racks, two sheet pans, a roast tray, and a digital thermometer.

The Ninja SP301 or dual heat air fry countertop 13-in-1 oven is a relatively recent addition to the Digital Air Fry Oven series. While it has additional capabilities, it cannot compete with Ninja DT251 in terms of functioning.

It still lacks genuine convection technology, but I feel it is a trade-off for its compact form. It's impossible to install a large fan in the middle of the rear panel without increasing its height. That minor modification would make it too big for an oven that easily flips away when not in use.

Anyway, we still like it as a toaster oven with many more features than its predecessor.

The Ninja Dual Heat Air Fry Oven's built-in griddle is a novel feature. They converted a sheet pan into a searing plate that also serves as a griddle. While your buns toast on the top rack, cook your thinly sliced meat on the searing plate. As a result, it's an excellent use case for creating subs at home.

So, what's the final word? The Ninja SP301 and DT201 are both wonderful equipment that can assist you in quickly preparing tasty dishes. However, if you want a machine with a Smart Cook System, the DT251 is your best option.