Oh, I loved those original cloth color catchers and did many tests using them versus terry cloth and such - whatever it was, they worked better. They've been the disposable type for many years -- probably because you need to keep buying them.
I've used the various brands, typically I get the Carbona large pack but I also got some from the Dollar Store and ran some tests and was happy with them too.
I don't put much faith in them picking up dye that is lost, I use them when I prewash to show how much dye is being cast off and whether it is in my comfort level or not.