We started with the Ninja mini, which just about cooks for 4. Ours is the older version with 2 lids - the second for pressure cooking. It does this well, with no loud hissing. If it's a joint, you can swap lids and brown it crisp - magic pot roast! Air frying is good - toss in a little oil first if not chips. Do your own spicy potato wedges. Also bakes well. Ideal for motorhome / caravan oven grill replacement. Also uses much less electricity than main oven or grill. Really excellent if you cook from fresh. Also, toast bread in toaster, then air fry with cheese, magic toasties! The new version has managed to keep pressure cooking but with just 1 lid
We were so impressed we also bought the larger maxi. This does not pressure cook, but adds a ridged grill. This gives chops burgers chicken etc a low fat barbecue flavour. Without grill plate is big enough to roast a joint, bake in a dish of your own, roast vegetables, and air fry larger quantities. Very versatile, includes meat temp. probe for automatic timing of rare, med, burnt, etc of all types of meat.
Both being closed in use cut down cooking smells, and air bourne oil and grease, so cuts cleaning. The devices are easy to clean too.
The one with pressure cook option is probably place to start. Download all the books and instructions and have a read. Instructions are good but cooking guidance could do with expanding a bit as not every food is listed, but you can usually fine something similar, and such guestimation has yet to give a problem.