Abrasive Medium...what's the difference??

So I'm looking at an SRD modular and, in case you don't know, it comes with two hard wool felt pads a scrub leather pad and a smooth leather pad along with some .5 micron diamond spray. I plan on leaving the scrub leather untreated and using the spray on one of the felt pads. The question is what to do with the other felt pad? Some people say apply CROx but that only seems to come in the .5 micron variety which is the same as the diamond spray...is there a significant difference between the two??? Should I go for a different diamond instead? 1.0 micron or .25 micron??? What are some pros and cons?
Also can the felt be used without any treatment and would it have any benefit?

Many Thanks!

I did a bit more searching on the forums and found that apparently the CROx has rounder particles so it can smooth out the edge of a diamond spray at .5 or even at .25 without sacrificing sharpness...I guess that answers my question.

I personally prefer CrOx to diamond spray as I find the diamond leaves a harsher feeling edge. Its also easier to overcook the edge on diamond as it cuts faster.