Yes I have one, usually against extra kitchen gadgets for taking up valuable worktop space, but it's in daily use. They are officially cheaper on usage bills than an oven, as is a microwave, but can't compete with an oven for some things, especially on quality of end product, and they can't do everything an oven can (Although the large and expensive ones can do more, as a friend of mine has a hi tech £270 one and does pies in his!!! 😮 ).

They have a tendency to dry out food, (but so do fan ovens) but I counter this with a sprinkling of olive oil on frozen chips, and they crisp up really well. The cheaper single draw ones like I have aren't too good for two or more things at once, like fishfingers & chips, it can be done, but you're forever having to stop it to move things around in the basket. For jacket spuds, I microwave then crisp up in the airfryer, much quicker and cheaper than the oven. It's a pretty useful addition if you have the space.

Thank you Alf, and it looks like I'm going to have to get one, if only for power usage, as I have a Bosch fan oven, which makes the street lights outside dim when I switch it on.

I liked the look of the Ninja one that Craig Charles demonstrates (funny too) on the previous page, via Stephen, which is £200 (9-1 whatever that means), and so I think the one your friend may have is the next model up (15-1 Wha?) which is £270.

You can get far cheaper yet decent air fryers than that.