We have a Delsey Helium Titanium carryon that is H 20.5 x L 14.25 x D 10.25 which equals 45 inches. I know that American says 22 x 14 x 9 which equals 45 inches.

How picky are they are a flight to Mexico on the size? We have never had the bag checked for size domestically and just wondering whether to take a different bag if it looks like we will have it rejected if it doesn't fit the sizer. At more than 1 inch more in depth, it will not fit even though the height is shorter.