The SendGrid platform and the team there kick mucho butt. It's a must have for anyone depending on transaction emails hitting the inbox. I've personally built an env that sends > 50m emails weekly, and it is a difficult task especially to hit the inbox. I've spent a lot of time with their team & they have many rock stars on staff, and Isaac is one of the most passionate people I've ever meet.
Sure. In my current co we have the email structure I defined and have white-listing in place, standard FBL's with all ISPs as well etc. And, the hassles when adding and preparing to bring up new IPs are a pain. When adding IPs on SendGrid they are available within minutes as needed, and they are immediately (within an hr or so) registered and able to report on SPAM/FBL reports.