White Collar and Heroes are definitely shorter than the others (all worth watching, though). I love White Collar--just the right mix of fun and serious, and seriously hot guys and a het pairing that most fans actually love. As I'm sure you've heard, Heroes season 1 was fantastic and it lost its way after that. I enjoyed it, but it did not hold up well. On the other hand, once LOST made the decision to end after season 5 (around season 3) it found its way again after kind of getting muddled in season 2-3 (season 1 rocked).