I love Ian's! It's such a Madison staple; I always have to stop by when I'm visiting family in WI. Ian's has such a fun variety...everything from mac 'n cheese pizza to baked potato pizza to salad pizza. Yes, salad pizza. I'm personally a big fan of the buffalo chicken with bleu cheese, but I like to try something new every time. So far, not a single experiment has gone poorly for me.
The atmosphere feels very much like a college campus. It can be crowded, noisy, and full of students. Depending on when you go (such as lunchtime), the line can get very long, but the service is fast and friendly so the wait is manageable. I highly recommend a trip next time you're on State Street.