Gate Check is GREAT
Our DS is 10 and DD is 3. They are both frequent fliers.
We always take our own stroller. No Bag Necessary (seems like a hassle to me).
Get a claim tag from the gate agent EARLY - not when boarding.
Push that kid(s) right down the jetway, pull him/her out, FOLD the stroller for them (that can be tricky for non-parents) and leave it there by the exit door of the jetway where the ramp workers come in and out. No need to wait for a worker, they will get it.
When you arrive, it can take up to 15 minutes for them to get the strollers up there, so no need to rush off the plane.
We are going to WDW April 8 to 16 and taking a nice big stroller from home! One thing though,,,,,,,,you REALLY dont want a big stroller if you plan on using the Disney buses to get around. We have a rental car, so it is ok. I have tried the big stroller on the crowded disney buses and its a nightmare and people hate you.
Have a great Trip!
