I recently purchased the Logitech Squeeze Touch(thanks to the TAS review) and I'm looking for a DAC under $500. I'm not sure how much of a sound improvement will I gain over the unit's built in DAC at this price range. The analog outputs are connected to my Simaudio I-3 amp. I've considered the V-DAC and the Cambridge DAC Magic. I have also considered the more expensive Simaudio 100D.