I am a big fan of colourising folders and files. I use colour labels in Devonthink to indicate the stages of a document in my workflow. I also use replicants a great deal. All my research pdfs will go into a journal article folder and I replicate the original document to other places in Devonthink according to my needs.
This was working well until I discovered I was having trouble identifying replicants with coloured labels applied.
The first screenshot is my use of colour labels. One of these folder is a replicant though I cannot tell until I remove the colour label.
This is the folder without the colour label. I can now see it is a replicant because it is in RED.
In Devonthink preferences you can turn off the colour for duplicates and replicants.
The result is a small double square icon placed at the end of the folder/file name to indicate it is a replicant.
Although I like to use of RED for replicants as they are quick to identify, I use colour labels frequently and prefer the have the colour label facility available with the double square icon to represent replicants. Flexibility is key to using this software.