Pillpack user here, and (unfortunately) an express scripts user.
I take 18 pills a day to manage some kidney issues I have, and Express Scripts doesn't have a good track record with getting your meds to you on time. If I don't have some of my medications, I could die. Not to mention, it's going to be a big pain in the ass to count out all those pills, AND take up a ridiculous amount of space with all the pill bottles, and pill trays.
Incredibly pissed off about all this...
Edit: forgot to mention my amazing feelings towards Pillpack. TJ (the CEO) has contacted me directly multiple times to make sure everything has been great, and every interaction I've had with them is phenomenal. If your insurance supports it, I highly recommend it.