I've had one for some years, and use it for most cooking as I'm on my own. Today, stuffed lamb's heart with potatoes, and broccoli cooked separately. Similar things to peregrina above. Shepherd's pie, both in the pan direct and in a pyrex dish. Toasted sandwiches. Ready meals of the sort you can't put in the microwave, and those you can.
I haven't tried sponges or other baking. It's the middle size, and I wouldn't recommend the baby size for complete meals. You can get a rack which raises things up - good for roast potatoes as they don't rest in the meat juices, and a sectional insert for liquids to help with full meals. Mine is made the wrong size, but those now available fit very well.
I use it on top of the cooker, and put the lid on the hob! The base of the pan also gets hot, so things can cook from below as well as above - but that is where I have had the couple of slight burns I have had.