I have yet to receive an upgrade either due to Platinum or RA status.
Maybe it's because I always check-in pretty late as I can't bear to spend more time than I have to in this uber-depressing Hotel.

The only thing I can say to recommend it - is that quite often the barrier is up / broken for the car-park & you can get free parking which is pretty good as you can walk to the terminal.
The downside to this is that if it is - it tends to be a complete "free-for-all" with people parking absolutely everywhere.