#3
#4
Great--thanks!
#6
Another one is www.seatcounter.com .
#7
Expertflyer is still my favorite and AFAIK, it is the only that allows one to see 'hidden' fare classes on Delta (i.e., upgrade inventory like Z, V, G). For about $10/month, it's really quite a decent deal. Seatcounter.com allows you to see hidden fare classes (including upgrade inventory) for UA flights (which is not available on expertflyer.com)