Q for season ticket holders...

I've got a parking pass in one of the Dome's lots and it's great. I lucked up and got one of the ones on the upper level (see if you can get one of those) -- that way, were out in the elements and can tailgate with an unobstructed view of the Dome, and not trapped in a dark parking garage with car exhaust.

Pros --
-reserved spot. No matter how late you arrive your spot is waiting for you.
-depending on the size of your car (the spaces are a little small) you can do some light tailgating.
-pretty easy to get in to the lot on game day.

Cons --
-Open flame law prohibits the use of grills and broilers. Really limits tailgating to cold sandwiches. Some folks throw caution to the wind and grill anyway (me included), but I have been shut down by the cops twice in the past two years.
-Not so easy exit. The cluster of people exiting all at once makes a nice little bottleneck which can seriously delay getting out of the garage.

Never sold a parking pass alone, but it does help sweeten the deal when you have to unload your tickets.

I love my parking pass. It has been well worth the $250 to have a secure, reserved spot to park on gameday.

Go for it!