I really liked that it was fully customizable for our business needs from color scheme all down until message content (which we had control over). The UI/UX could have been improved with more examples of how things should look in different scenarios - which would've helped us get started quicker as well! We were able solve some integration issues between 2 apps using courier messaging platform so far without any problems or technical glitches experienced at this point.- Integrate data coming out off an SPA into MailChimp- Sending emails via Gmail account instead of SMTP directly when sending bulk mailings. This allowed me not be concerned about my server being blocked by spam filters since everything goes thru Google's servers first before anything else happens after hitting GMail inboxes. It also made sure there weren't too many steps involved if you're new to setting up smtp settings properly but.