I've used Sendgrid quite a bit, it's great! But in this particular case, you may note I specified it needs it's own inbox: This particular tool of mine does presently use IMAP for inbound mail, and even though the volume for it is insignificant, it means I generally need a "real email account" for it.
Oh, right, sorry! I misread that as something along the lines of “sends to my own mailbox”. Perhaps replying on HN first thing in the morning wasn’t such a bright idea haha