M-Audio Fast Track C600 by dans595
I only owned the C600 for a short period of time, but it made a notable impression on me anyway. I have since upgraded to the RME Babyface. Compared to the Babyface, the C600 has a similarly appealing overall sonic character and tone. However, of course, the detail, quality and quietness of the preamps is not at the same level.
I did prefer the C600 over the Focusrite Forte myself due entirely to the way vocal recordings sounded when made on the C600. To me, they simply sounded better (though less immaculate).
The unit is absolutely beautiful, and has plenty of I/O on the back for running lines in and out. It features midi in, two headphone jacks with independent volume controls, built in DSP effects, etc. You also get the reliability that goes with an M-Audio unit: extremely stable drivers, never any connectivity or reliability issues of any sort.
I found mine on Ebay "new" (it turned out to be used) for around $350. Presumably that means you can really find new ones for about that price. At that particular price point, I think the interface is an absolute steal. I wouldn't consider anything else in that price range.