Three months ago, I posted an extremely negative review of our four Champion toilets, which were installed in 2004. We had repeatedly contacted the company for replacement parts, but those parts never solved the problems. I mailed a copy of that review to American Standard, and was contacted by a customer service representative. The company has redesigned the "guts" of the tank (they needed to; the old design simply didn't work!), and they shipped four replacement kits to me. The kits have been installed and, so far, are working well.
Suggest people who have been going crazy with these toilets the past few years contact American Standard for the NEW design.