What I'm going to be using the unit for is recording some songwriting ideas and then editing and producing them in Garageband. I then take that product and use it as a sketch for the professional studio that I go to approximately once a month. Having only one input is fine for me as I record one instrument at a time. I actually like the idea of the internal microphone on the One unit to as it will help the quick sketch ideas. The price difference is $300. My questions are: I have a set of studio monitors that I mix on as well as listen to mp3's on (Dynaudio's). I noticed that the Duet has "4 (Stereo headphone out & L/R speaker outs)". From what I understand the One only has one output then a splitter has to be purchased to allow for the monitors. 1) Would having a splitter effect the sound quality or the panning of the music when I listen back? Will it have any other noticeable effect? 2) The Duet has balanced speaker outputs while the one has unbalanced. Is this important for my application? So, which unit would be best for me?