I love all apogee products and would highly encourage saving up for it if you ca (especially for your limited simultaneous I/O needs). Super pristine pre's and converters.
That being said, if you dint feel like dropping $600, I might like into some interfaces made by focusrite. They have a similar interface to the duet, which is the scarlett 2i2. It has award winning pres and the sound quality is still superb. In addition, It may come with a plug-in bundle from focusrite and will end up costing you less than half of the duet. (I believe it goes for $259 at guitar center or sweetwater.