Go there and go the the knowledge base area. It is a wealth of info on all sorts of cartridges and tests and info. I stumbled across this and it is fantastic. Just wanted to share it with you guys as sort of a way of paying back the great help I have received. It really is great. It goes through different cartridges, history, specs, etc. I have to say it is the best info I have found on the subject. (and I waste a lot of time looking for such info.)
Thanks and check it out.