They don't allow you to double up on their free trials. The price changes between their different tiers, however; there are options cheaper than $22.95.
I signed up for the 14 day free trial, with 2 games out at a time. I went to cancel it, and they offered to let me keep the membership for another month at about half the normal price. So I only paid $!2.xx for a month with 2 games out.