I was part of express scripts many years ago and was extremely satisfied. However, my fist experience with this mail order service since the has been a nightmare. I was left without my medications for what they considered issues 2 issues with my medications. They withheld 3 of my medications for which they did not have a problem with. After 3 weeks many phone calls and hours I request that my physician call them. When my physician called them he was told that they knew the dosage for the med in question and they no longer had a problem with the second question. Did they withhold my meds on a whim? Your guess is as good as mine.