I work at the airport and use the shuttle every day I have only waited 10-15. Keep in my mind that they take their breaks at various times but there is always another one pulling up. At the terminals it is a little different because it tends to be a lot of traffic so I have to make myself visible.
If you are standing in the right pickup place, which changes, they will get you fairly soon. You must text them. They will not answer phone calls. Only used them twice, but, I will probably use them again. Parking spots are small except for the roof.
Watched multiple rounds of every single other garage shuttle go by before getting picked up after a long wait. It's true: they don't have enough shuttles, don't answer the phone, and the spaces are compact.
If you need to get to your car quickly and will arrive after 11pm, this is not the place for you. Despite calling, texting, standing in the correct area, I waited for an hour for a shuttle. It never came. I had to flag down a competitor (or three) to get a ride to my car. I noted the names of the parking companies whose shuttles were running. I specifically chose this one because of the proximity. I paid more for worse service. Worse than waiting, the person who did answer the phone the second time, hung up on me because she did not appreciate my tone. And when I finally got her back on the phone she admitted that she had no idea where the shuttle or driver were as no one was answering the radio. Never again.
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