Hm, I noticed that the Oaded box, when it clips (red), does so pretty gracefully in terms of kinda smoothing the edges for less of a gnarly popping horror sound during overs. It has to be pretty severe to be audible; however speakers don't like reproducing squared wvase one bit.
I much prefer not rely on those characteristics and simply avoid clipping by running more conservative levels.
If you bust out yer wave editor and zoom in on a peak that hits zero, you'll generally notice the top of the waveform squared off - which is kinda smoothed out (less square) on the Oaded box.
As for the pad, its just a 20 db rolloff, which lets you run the gain knob higher at loud shows than you could without it engaged.
90% of the shows I tape do need the pad. I don't believe it affects the saturation characteristics as such.