I strongly prefer separate columns to colour coding, it takes longer to look though and find available farms/which rare weapons are available this way.
Heres why i say 1 column is faster.
2 lists
I look through the list of names for Icybreaker. I dont see him on the rare farm list. That doesnt mean that he doesnt have a farm though. All that means is that he wasnt posted as one. So I go to the none rare farm list. He isnt there. So what does that mean? he was currently mia, so no one knew what he had, or that he was in pvp.
1 list
I look through the list, scroll down to the I's I dont see icybreaker. So no one knows what he has. Nice and simple.