Not yet, shortly after purchase I threw in a 2 TB drive and haven't quite filled it yet. Alas eventually I will likely go the external route. You're reading from a guy that put a 4TB external on his WiiU.
Unlike others I do like to horde my digital games, nothing like scrolling at hyper speed for 40 seconds to get to your Library icon. I have already moved all the crap unused icons into folders, I want that 40 seconds of scrolling to be nothing but games zipping past.