I know others are saying otherwise, and they probably know more than me, but I find it incredibly weird for a pressure drain fitting to be on the supply side. Why would that be there? The pressure should never be getting that low there and even if it does, you don’t need a drain because the supply side should be buried deep enough that it doesn’t need draining for the winter anyway.
Man we need a giant comparison table. I looked into these but have been trying out SiYuan.