I prefer Pioneer because of the presence of the SuperTuner's on those units. They do require a ~$30 adpter to give you in/out access to the IP-Bus port (CD-RD10), but aside from that I love both units I've had. The first didn't have IP-Bus on it... The most impressive part has definitely been the tuners especially being able to pull in fringe FM signals that are of passable quality to listen to.

The other aspect I like is the simplicity (of some of) the line. So many head units these days have nothing but visual noise going on and there is little appeal to their presentation.

My $0.02,
Tim