Yes... I love this series. I bought it on the big DVD pack with the complete first season, because it isn't available in German television right now. Anyway, I love it because it's not only the concept which makes it thrilling, even without that real-time style it would be extremely exciting and suspenseful. Also, it stars one of my top ten favourite stars, Kiefer Sutherland, and a truckload of exceeding supporting actors. Elisha Cuthbert, Leslie Hope, Sarah Clarke, Xander Berkeley, Dennis Haysbert... I could go on forever, even the characters who die after two episodes are very convincing.
Overall one of the things you can't stop watching after you've seen five minutes of it.