Is a combo like this as good as a dedicated griddle?

No. A dedicated flat-top gives more even heat and a larger cooking surface. The combo wins on space, not on griddle performance.

Can it bake pizza well?

The pizza chamber gets hot enough for fast bakes, but its floor size limits you to smaller pies. Expect Neapolitan-style results rather than large family pizzas.

Does the air fryer match a countertop air fryer?

It is closer to a convection oven basket. It crisps fries and wings fine, but a dedicated air fryer heats faster and holds more.

Outdoors, on a patio or deck. It is large and heavy, so plan a permanent spot rather than moving it for each cook.

What should I check before buying?

Confirm the fuel type, the griddle and pizza chamber dimensions, and whether the air fryer basket is included. Those details decide whether it fits your patio and your cooking.