SkiAdcock, I think you're referring to ParkOne. To my recollection, their rates were a bit higher than the Parking Spot ($14.95+tax/day, as opposed to $9.95+tax/day for rooftop parking at the Parking Spot). ParkOne's location is killer on the outbound, but it can be a bit inconvenient on the return if you have heavy bags & have to wait for the shuttle to drive around the huge expanse of the parking lot to get to the shuttle stop closest to your car.
They do have a website (parkonelax.com - sorry, too computer illiterate to figure out how to post a link), which lists a frequent parking program & has printable discount coupons.
Point to note: the Parking Spot has a second location on Century Boulevard, which would probably be the more convenient location from the 405N, unless you plan to head up Sepulveda & grab an In -n- Out burger on your way.