Really? I find Gmail too unreliable. My partner has been fishing our private communications out of the spam folder for years and recently I posted a complaint about mail sent to my Gmail account also ending up in the spam folder regardless of whether it was confirmation of a sale, retrieve password or a newsletter. No, our server is not on any block lists and while their support was exonerating their service a client reported that Gmail had returned email addressed to us marked as "email address does not exist" claiming that is what our server had reported. Well that email address has been in service for several years. Who needs a mail service like that?