No. I use it a great deal, but not really for just heating up pre-cooked food. Mine is a micro with a grill and I use them both a lot, sometimes both in the same dish.
These are some things I use it for :
Defrosting chicken, fish and other food ready for cooking.
Softening butter, spreads, honey and ice cream.
Heating up gravy, sauces, custard.
Finishing off partly-cooked ciabatta, garlic bread and rolls.
Heating up fast-food or take-away food that's gone cold.
Grilling pies, pizzas and flans.
My OH uses it to 'warm up' icy drinks from the fridge when they're too cold.
Cooking jacket potatoes.
Making pizzas from a base and adding my own toppings.
Heating up beans, soup, tinned vegetables.
Defrosting bread and rolls.
Making scrambled eggs.
Heating up tea and coffee that's gone a bit cold, instead of throwing it away.
Cooking chicken and tuna fish.
Melting chocolate.
Many other things.
I don't even have a conventional oven. When we moved into our flat, it had a tiny kitchen and we were going to wait to get an oven. In the meantime our friend gave us an electric baby Belling type double electric ring, and what with that and the micro, we managed so well that we decided we don't need an oven. I do Christmas dinner, with the whole lot of trimmings, and all our meals, on the set-up I have.