OT - which off-site BWI car-park?

[agnes!]

I also posted about our BWI parking dilemma over on the Transportation Board but am hoping for some more responses here. We won't be using the on-site Express Shuttle Parking since they aren't running their special coupon any more so we've decided to try one of the other door-to-door services, it will either be FastPark or PreFlight. Anybody here use either one and have good or bad reviews? Time is of the essence, if you have experience with one or the other, post here post-haste .

Thanks,
agnes!