With the advent of multiple virtual hosts per site, it should be possible to create criteria based on this fact.
Users are segmented by the hostname
- a segment with criterion hostname equals "my.liferay.com"
- the hosts configuration of your system has that domain pointing to your local
- the site contains a page with different content for the default experience and a experience for the segment
- When the page is visited using the hostname (instead of localhost)
- Then experience is shown (instead of the default)