Farm 133 - Which one should be premium?


I've installed Farm 133 theme pack into one of my WPMU site. As a matter of fact, rather impressed with the themes that are included in the Farm 133 pack.

I believe one of the objective of Farm 133 is to offer some themes as premium themes that are available for Supporters only. Is there a recommended list of themes (out of the 133) that should be premium? Or is it better to offer all 133 themes to all members including free members?