Casbah (and Eleven, and others in the chain) is a typical American high-end restaurant: average food, high prices, expensive drinks. The focus is on profit maximization of the Restaurant Makeover variety, not on a passion for food. So the food is so-so, but expensive. Portions are large, though, so you feel you've gotten value for money. I dare say they rarely deliver a bad experience as the emphasis is on repeatability (but I've only been here the once). Service was good.
There are much more amazing - and cheaper - places to try in Pittsburgh.