i agree with dave, i took the oam calipers off the other day and couldnt beleive how much they weighed, they were heavier than rs4 8pot calipers, the up side is that the oem discs are a fair bit lighter than the rs6 discs so works out to be pretty much even in weight. if the discs come in at less than 3-400 pounds then its a good value upgrade but any more than that then other routes must be more worth a look at...