I've been to the Benedum plenty of times (all for musicals) and I've always had a good experience. Being a fan of the theater, it's always fun to put on some nicer clothes and see a show.
The theater itself is beautiful. Complete with a huge chandelier and detailed ceiling art, the place itself is a sight to see. The hallways and staircases are a bit old, but it gives it a nice vintage feel to better your theater experience.
One complaint I do have is the "lobby" area is kind of small making leaving the theater a bit of a hassle. Not to mention, the merchandise and snacks stands are there as well, making everything even more tight.
Also, just a little tip... Being a college grad paying my student loans, I unfortunately don't have enough money to get front row seats. I usually buy the bargain seats in the back for $10-$20 dollars. What's cool is once the show begins you can move up to seats that aren't occupied. You may pay $10, but end up sitting in a $40 seat. However, be prepared to be a little lost. It's hard to hear what some of the actors are singing due to being way up at the top and not being able to read their lips. I'm sure the sound feedback has a lot to do with it as well.