Carls is pretty much a legend in the Monroeville area, it's been there years. I went the other night with friends for dinner and enjoyed it.
I had the Carl's Burger which is a 1/2 pound hamburger and was pleasantly surprised. It's not a Tesaros burger but pretty good for a bar burger and reasonably priced as well.
They have a very big menu for a small bar; if you plan on going on Saturday night, come early, the dining area only has 6 booths.
I'll be back.