Mixed feelings about WallyPark Premier. It's covered, park-and-lock, and secure. But the shuttle doesn't drop you at your car; you have to hike and use stairs / elevator to find it yourself. The ride to the airport is very long - you head the wrong way on International Boulevard, wait for a long light and make a U-turn, etc. And without the aforementioned discounts it's expensive.

Used it once or twice, went back to ShuttlePark 2.

Off topic: agree with the tangent upthread about the ridiculous new rental car center, the worst thing to happen to SEA in a long time. Besides being expensive and very time-consuming to use, it's incredibly poorly designed; why force customers outside to use the access-to-cars escalators in a locale where it's raining all the time? I was dropped there last summer to pick up a car and got hopelessly lost. Sincere apologies to all SEA visitors for local idiocy.

Sorry. Rant over. Back on topic.