Chris,
We send out a weekly newsletter with all of our content updates. Our opt out is right at the top of the page, so it's the first thing you see. That appears to be the most important thing with spam complaints. As soon as someone hits that button, I MANUALLY remove them from our mailing list so no mistakes are made.
On several occasions we have been approached to BUY more emails or to advertise for someone else IN our newsletter. We simply refuse this every time. Our newsletter is strictly for our promotional purposes and ONLY goes out to our past and present clients.
To the best of my knowledge, we haven't received any spam complaints. (Since I've been with Xamo

)
I personally get about 100 spam emails per day. If I have the time I'll unsubscribe from them, but on most days I don't. The ones that annoy me are the ones that ask you to reply and then they bounce back with an unknown mailbox. Those fuckers should die.
Ron