Item Categories

Is there a limit on the number of values for an Item Category or does the form Category Codes limit the number of rows you can insert? Or could there be a limit of rows in the Category Sets form?

I am looking at setting up a custom Item Category that will have over thousands of values--need to know if there is a limit that will keep me from using this approach.  Will then have to setup a custom table for cross-reference between the values and the item.