Thanks John, I think I'd read that thread somewhere in the last few days, but it's a good succinct explanation.
One thing I am curious about with the sulfur system is the whole carbonate reactor part. You generate acidic water in your sulfur reactor, so it's recommended you run it through a carbonate reactor (basically just a bucket of crushed coral) which seems fine and good, because most of us do that for buffering anyway... but wouldn't you be dissolving an abnormally large amount of calcium carbonate this way? The acid gets neutralized, so your pH doesn't go off the charts, but it seems to me your GH would go nuts. This is OK in a reef tank, or a snail tank or something, but I'd wonder about it's effects on the average aquarium.