There are few limitations that would be addressed in future versions
- Duplicate fields
- Radio buttons ,but a drop down list could do the same job
- No support for multiple drop down list ,but using check boxes is a good alternative
- For each field there are options that could be used to populate checkboxes/drop down list;
Updating an option in the option lists would cause lost of save data for a post.In other words when you
save an option while editing a custom field ,if this option value is changed later on then all post fields that have this value
selected for their field would loose this value.So choose you list values carefully.