Cleaning the Convertable Top?

lifter 1 top cleaner spray (in a can) does great for cleaning. i dont if its still on the market though, i picked it up out of the closeout rack at o'reilly auto parts for a buck and some change.
bluemagic top cleaner seems to do a good job at protecting as well as cleaning. it turned my washrag black, but i really couldnt tell a difference other than gloss.

heres before/after a can of lifter-1:
IMG_0634sz.jpg