I have made Wally Park my preferred parking choice. Why you ask? I will admit, they aren't the cheapest, but sometime going cheap can backfire. I tried to book using some other sites but kept seeing issues or glitches that didn't appeal to me. Whether it wasn't their advertised rate being for real or issues with their website or just seeing how long it will get to the airport. I like being to the airport within 10 minutes from time of pulling in to drop off, not 25 or 30 minutes as advertised with places.
Other reasons? Their customer service is fantastic, they offer a wide variety of discounts opportunities (Frequent use, groupons, AAA, military, and Senior) as well as a frequent parking card. In addition, they are hands down one of the most social media friendly places I have used. They are right up there with Alaska Airlines as far as twitter use and being feedback friendly with quick responses.