Ninja
Foodi Dual Zone Series
Dual zones for smart cooking, but baskets are small.

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I have the Ninja DCT-451 toaster-air fryer double oven and love it. I've used most -- but not all -- of its functions. This week I roasted chopped walnuts in the lower oven, hastened the ripening of 4 bananas in the upper compartment, and then baked a banana walnut loaf cake in a 5" x 9" Le Creuset enameled cast iron loaf pan in the lower oven. Before this month, I had never baked a cake in my prior eight decades. My friends and I agreed that the banana walnut loaf turned out delicious. I frequently use the air fryer function and its basket to cook many items and have been pleased with the results. That being said, I have no experience cooking with a dedicated air fryer, so I cannot compare the two approaches. A bonus point is that this device uses a lot less energy and generates considerably less heat than using my regular large oven.
I'm not a big fan of the ones that seem to be the most popular. You should buy the largest one you can afford and have counter space for. It's really a convection oven and if you have the room you could cook a chicken I have the Ninja dual oven where the bottom is an air fryer in the top is a toaster oven, I don't use it everyday, I use it several times a day I also received as a gift one of those that has the three stackable trays. It's okay but you have to rearrange the trays from time to time if you're cooking something that takes a while. And yes I do use both
I've got the Ninja dual oven with the little bitty top door you can open separately. I like it a lot.
Look at the Ninja Crispi Pro models that have glassware baskets. They are pretty good. Much easier to clean and you open them up less to check the food because you actually see your food. I have one and like it more than my other model Ninja that is a 9 or 12-in1 thing
I have the Ninja 12-in-one. I use the regular oven when whatever I’m cooking is too big for the ninja.
Can’t say I’ve tried any others but I’ve never had any issues with my Ninja. I have the one that’s stacked instead of side by side to save counter space and I love it. Only complaint is the cord is a bit short.
Ninja
Foodi Dual Zone Series
Dual zones for smart cooking, but baskets are small.

COSORI
Turbo Blaze 9-in-1 6QT
Quiet, easy to clean, but lacks a viewing window.

Ninja
Foodi Air Fry Oven Series
Flips up to save space, but shallow and air fries poorly.

Breville
Smart Oven Air Fryer Series
Oven replacement; spacious, but air frying and cleaning divide users.

Typhur
Dome
Self-cleaning and quiet, but expensive with shallow interior.

Ranked #1
Ninja - Crispi Pro 6-in-1 Countertop Glass Air Fryer

Ranked #1
Breville - Smart Oven Air Fryer Series

Ranked #1
COSORI - Turbo Blaze 9-in-1 6QT

Ranked #1
Ninja - Crispi Pro 6-in-1 Countertop Glass Air Fryer

Ranked #1
Ninja - Foodi Air Fry Oven Series