I understand your suggestion but then again the user has no ability to easily iterate trough all styleClasses - and we would need additional methods like removeAll and probably something easier to access each single style class (I reckon it would be messy to let the user split the styleClasses NSString). I would like the minimal approach and expose a (readonly?) collection of style classes. If the property is readwrite the user has also a more sophisticated way to assign multiple properties instead of calling ```- (void) cas_addStyleClass:(NSString *)styleClass``` or messing with concatenated strings. 

 I am thinking of use cases like "remove all style classes that contain a specific phrase" - it is just more flexible with a set I think. I will implement ```- (BOOL)cas_hasStyleClass:(NSString *)styleClass``` today.

 What are the cons of that solution why do you suggest to hide the collection?