The problem with using the email to text gateways from the cell phone providers is they have recently started putting all kinds of antispam filters on the gateways that block any sort of suspicious messages and you can't count on them working all the time. I'd been sending texts from my Crestron system for years through those email gateways but they just got too unreliable so I looked for another way. My alternative is to have an old Android phone on a $8/month account with US Cellular. Using an Android program called Automagic I can send a simple HTTP Get request from the Crestron system to that phone and it will trigger an event that sends me texts on the cellular network directly. This has been working well for a while, though it's a total cludge.
I would also send those same messages via email at the same time, but that got snarky as the email providers put up stronger measures to stop the spammers from using their SMTP networks. The Cestron emails don't seem to have all the authentication data that Comcast, Gmail and others want to see to accept and send emails. I set up a free Sendgrid SMTP account and that's been working well for a long time.
