Without insurance or the coupon it's $1600/month. With insurance it's $650/month. With the coupon and insurance it's $0/month.
Amazon is the only pharmacy that didn't mess up the insurance. They also autoship on time every month. I'm not even joking when I say that I actually cried over how difficult it was with other pharmacies.
Clearly they were spending too much money on it. The idea is for there to be no interaction other than a payment/delivery cycle. If there are plural positive interactions the overall system was poor (needed multiple interactions) and staffing too expensive ("best" rather than mediocre).