To be honest I didn't remember such bass extension and clarity from the Hex.
I've started with one of favourite album of the 2014 (take a look here, it's an amazing album) and I didn't remember the cello to be so clean and punchy in the first track, and believe me, I've listened to it quite a few times! Also, I was struck by the ambience of the recording and the depth of the stage.
I didn't expect this kind of improvement, it's not a nigh and day change, but noticeable and very welcome. I've exchanged a few emails with Cees at Metrum and he said the biggest benefit of using the nee USB module was of course the ability to plug and play the device in Mac OS and Linux (I use the latter), but he did mentioned some jitter improvement too.
Maybe I'm tricking my mind with some biased expectations but in the end I feel I didn't waste 200 euros :-)