My family and I love Legos, but found Legoland to be a real disappointment. And I'm not just talking in comparison to Disney (which of course has the theme park "thing" down to a science). That being said, if you're in L.A. for a lengthy trip, want an amusement park experience, love Legos, and don't mind the drive then Legoland might be worth a day. Just calibrate your expectations REALLY low, and you'll probably be okay. The rides are okay, the lines are okay, the staff is okay, the cleanliness is okay... you get the point. Go in with low expectations and (hopefully) you won't be disappointed.