Gremraf said:
He is trying to keep the kids from viewing stuff he does not want them to see.
He is trying to find some channels that constant monitoring isn't needed on.
None of the premium movie channel packages fit that description.
The biggest difference is that Cinemax, HBO, and Showtime have more movies that rely upon sex and violence to attract an audience, whereas the mature material on Starz is more likely to be in a well-reviewed "quality" film.
For example, I see "Grindhouse" and "Superbad" on the Starz schedule. Both movies contain scenes and/or language that most parents wouldn't want kids to watch, yet these movies got good reviews and made millions at the box office. The mature scenes on Cinemax are likely to be contained in movies with titles like "Co-ed Confidential" or "Hotel Erotica."
So there is a big difference in the tone of the channels, and Starz is less likely to cause parent panic at any given time, but all the premium packages would require monitoring in most parents' view.
And as someone pointed out, both HBO and Starz has "family" channels.