Performance Quiz #10 -- Thread local storage

It's time for another quiz!

A very short one this time.  If I need some thread local storage and I might need several entries should I use:

Thread.GetData(slot) and Thread.SetData(slot, object)

or should I make my own static member like this

 [ThreadStatic]
 static Dictionary<String,Object> myItems = new Dictionary<String,Object>;

and get things through the dictionary?

Warning: spoilers below in the comments ... already :)  Maybe my quizzes are too easy :)