We can agree to disagree here. You have no recourse when one of the Sendgrid shared IPs you are using gets put on Spamcop. Sendgrid might get around to working with them to remove it in a couple weeks. You also have no way to eliminate that IP from your pool of IPs. So in my case about 40% of reports I was sending out were getting blocked at the email server of the receiver. Buying a private IP is your only recourse. Unless your emails don't matter, in which case it might be fine to lose 40% of them.