I've been wrestling with this for some time now and am about to give up. MS advises that we create all our site collections in one web application and supports both host-named site collections and path-named site collections in the same web app. Cool. But I can't figure out how to make that work with My Sites.
I can set up the HNSC and configure all the My Site settings but when I go to enable Self-Service Site Creation on the web application I can't reference any FQDN. All it shows me is the name of the server (SPDEVSERV) which is what I bound the HNSC to originally.
Is there some trick to getting the self-service site creation to recognize the URL of root site collection in the web application?