We rented from the GF last Aug and I think WL has them as well. We used the coupon from the package (I think it was get 30 min free when you rent for 60 min ?) . Basically, they let us rent 2 for 45 min for the 60 min price!
Each adult took a DS, so we were all out on the water at the same time. It was pretty busy though! Lots of other sea raycers, the ferries and smaller boats too!