Well, make sure they go potty at the airport before you go inside, if they are pad trained, carry a few pads in case they need to go and I would take Gucci into the big handicap bathroom stall and put the pad down for her, or the family bathroom..
Typically, last call is an hour or so before we leave and I limit the water through the trip.
I love the petego bags, I've never tried the other one, but they both look nice. I like shoulder bags with pockets to store stuff, and I normally use the stroller at the aiports and then put her in the bag right before we board, check the stroller at the gate and then grab it back on disembarking .
She might surprise you and be quiet and attentive with all of the people and smells, and maybe she'll follow the lead of her bff, that is bound to help having another dog there that is calm about it.
Gucci's fine, she just hates the loud noise at take off but other than that...
Oh,, or if someone near us bring fried chicken on board then that really drives me crazy because she drools and cries for it....
Other than that smooth flying!
Enjoy your trip!