I already have my own smtp server, which is the one I'm trying to use. I also have SPF, DKIM, and DMARC fully set up. I also run my own DNS server. I've actually already left Gmail now. I'm switching my users over to Thunderbird as an email client, and using Mercury as the server. So far so good. By the way, across different Gmai laccounts, the exactly same settings are garnering different results. Something in Gmail's sending is truly broken right now. It's intermittent at best.