Cloud providers are not as bad as you'd think. I've tested several DO IPs using various checkers, as I've been thinking about moving my server there (currently at prgmr.com), and they have all been clean. SPF and not being an open relay seem to be the 2 important things to keep you off the blacklists. I still don't have DKIM (been on my TODO for a while... but lazy) and haven't been put on a blacklist in many years.
I used Digital Ocean for a year. No problems, never sent spam. Then my mail started being spamfiltered, apparently because a neighbor was spamming. Seriously don't recommend using cloud hosts if you care about people receiving your email.
Hmmm, thanks for that. I just checked my CloudAtCost VM, which I'd never have considered running outbound mail from, and it's not on _any_ of the 90+ blacklists mxtools checks. This astounds me!
