I'm assuming that when you say portraits, it's professionally? If it's not, I would say get the S2. It does have "out of the box" pleasing color. For professional use, D100. Shooting in mode II Adobe RGB simply gives you a wider color gamut, but you have to consider using a calibrated workflow. And I don't mean custom curves, <<view the threads>> I mean profiling your camera to IT8 or Macbeth Digital Color Chart standards. This is something you should consider if your going to output your prints to something other than inkjet, or just look at them on your screen. S2's have a higher Delta E correction than D100's <wider gamut error to correct> . That's why I chose the D100, it was simply easier to incorporate into my color workflow. As for the type of portaiture, I do a lot of commercial head shots for magazines and publications. I either let my clients view on screen, or give them inkjet proof sheets. After retouching, I give them an inkjet proof before sending it to the lab for "photographic" output. The inkjet's HAVE to match whatever output the customer needs, and all that starts with predictable color and output, and that can only happen with a calibrated workflow, and for me that starts with my D100.