This place is one of my favorite places to hang out in Pittsburgh. I never really bowled until I started coming here, actually. And now here I am, 4 years into being a bowling league (still a crappy bowler), and still loving this place.
I bowl with the Pittsburgh Sports League, which has been hosted by Arsenal for bowling for as long as I've been involved. That's been a fantastic experience in itself.
For the non-league experience, it's old school social bowling. A bar that happens to have a bunch of bowling lanes. Come on one of their deal nights (which I think are basically every night) where you pay a cover and get unlimited bowling, cheap drafts, bar food, and great cocktails. You get the old-timey feel of a bowling alley, the lanes are well maintained, and the staff are great. I can't come up with a single bad thing to say about this place (except that parking is terrible in Lawrenceville).