I've just bought my first Tetenal E6 kit as my Agfa kits are probably too old to use. There is an intersting warning in the instructions that "certain types of plastic absorb traces of the colour developer strongly and permanently". I use a Paterson Auto Colortherm and never had CD absorption problems with the Agfa kits. The plastic cups in the Paterson are made of a pretty rugged plastic. Has anybody here experienced this with the Tetenal kits?