I've owned both, I prefer the pitch black. Thought the next tuner I buy will be a ST-200 Stomp Box Strobe Tuner
+1 ... I have the Turbo Tuner. It is slightly more expensive than both, but then again it's a real strobe tuner vs. the peterson which is a virtual strobe tuner.

It's what I got when i emptied the bulk of my college spending money the summer before I went.
It's a fine pedal tuner, roughly the same price as the Korg, almost. It isn't black and sleek (but it could be If I ever got the initiative to repaint it and claim it to be a TU-3). Hey, it's what I got when I started off, so that's why I like it (plus they last forever).