We attempted to use Mailster, a mailing list system, but found that when we used Mandrill a duplicate message was sent back to the list mailbox resulting in duplicate messages being distributed.
I'm not sure how, but my guess is that Mailster is including the From address in the header, and when the message goes through Mandrill, mandrill is seeing that incorrectly and sending a copy back to the originator. I really don't know.
But I was looking at the template overrides--which is really cool--and noticed it could be assigned to specific components. I didn't know if there was a way to have a component blacklist per se, where it would use the Joomla mailer settings instead.
Thanks much,
Kevin