that tells you something that they no longer supply the steel ones. One of the nice things about the rubber type is that you can slightly over tighten the chain and the rubber gives a little buffer, especially if you have a tight spot on the chain run when you check at various spots.
You can't do that with steel on steel. These are also available for the Atlas/ P11 engines.
Using the rubberized chain tensioner and the Andy chain timing chain is what I would recommend.