Clayton,i payed around $400 brand new (08-20-2011) if this help you any to price your used one.it's probably more valuable to you,to just install it though imho.massive improvement.
Gary,thanks for sharing that experience.this has been an ongoing issue with my rears not self adjusting worth a darn,even though everything is brand new in there.im running the stock master.so sounds like i should upgrade it to the f-super's then.