Best flight stats site

When my inlaws flew in and out last week it would have been nice to know about this site: http://www.flightstats.com

It's the flight arrival/departure stats site for all time.  Not only does it show estimated time of arrival/departure (of course), it summarizes the weather info, and everything else known about that flight.  What's its historical on-time arrival performance? Are there any other delays at that airport right now?