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I have experienced no ISP-related issues for self-hosted mail on Rackspace, Linode, and Vultr in U.S. DCs.

Note that I've heard Vultr in EU requires trouble ticket to open mail ports.

What about bigger hosts, such as AWS and Google Cloud?

I really don't have any experience with them.

You have to fill in a form to send email from an amazon EIP, but generally delivery from Amazon IPs is poor.