In my experience the main thing to look for in an air fryer is cleaning
Can you reach and clean ALL the areas that vaporised fat will go
The main area I have had problems with it up around the element and where the air goes once it has passed the food
We got a Ninja recently and it is the first one that I have been able to clean reasonably well
(you should see the state of the daughter-in-law's one - minging and then some!!!)
anyway - good luck
I have the Ninja.
If I cook anything 'fatty' ie sausage or bacon I put some foil underneath. Saves any mess.
I find that things like chips only require a wipe down.
If the trays start to look iffy I soak them in a bowl of soapy water (maybe after washing the glasses).