American Airlines Comparison

[mermaid&cinderella]

I have always flown Canadian airlines, oh I did fly American once, but it looks like we will probably fly out of Buffalo in December and I am so unfamiliar with the US airlines. Can someone post the difference in respects to comfort, baggage allowance, baggage cost (if any), advance seating price, etc .
AirTran
JetBlue
American
United
Delta
SW

Also has anyone flown out of Niagara Falls, NY Airport? They have Vision Airlines, Sprint and Direct Air. Does anyone have an experience with these?

 

[Ted in Halifax]

Bag Fees (1st bag)

AirTran 15
JetBlue 0
American 25
United 25 (23 is paid online)
Delta 25 (23 is paid online)
SW 0