One shows the output in % of each CMYK value (10% C, 50%M etc.) where the value shows the numeric value of each (10 C, 50C etc.), Both examples here will give different outputs as 10%C and 10C are completely different but from what I have seen it doesn't make a difference as to which you choose as it is only a display option. I work in % so I have it set in % so I know the % are the same across adobe and onyx.
Chaz