Most tolerant Email Service Providers for grey hat methods?

Hey, I'm looking for ESPs (email service providers) that tolerate grey hat methods (cold email campaigns, automation, grey mail) .

From your experience which of the following ESPs best fits the description.

SocketLabs
SendGrid
Postmark
SparkPost
Mailgun
Mandrill

Brevo from my experience is quite good

Do you send from a shared IP? because dedicated IP is quite expensive in brevo.