Which particular model you get is highly dependent on time and day of arrival and the fleet mix. You did not indicate when the reservation is.

I've done a few SFO rentals recently and they have had a lot of new arrivals, which is refreshing the fleet. They were so full of cars, the Presidents Circle line was partially blocked.

When you have Gold, you can always go to the gold office and ask them what they have in inventory. I was assigned a Chevy Cruse the other day and insisted on a full size. Ended up with a 2015 Charge with 500 miles on it ^

Do be aware, SFO is very aggressive about selling upsells.