has anyone heard about the possible issues concerning the new line of AFR "eliminator" cylinder heads?? i have heard that some of the heads are experiencing valve issues, apparently the stem of the valve is mushromming. I am about to order a pair and am wondering if anyone else has alreay bought/ordered a set or if they have any other info. i guess AFR is going good for the issue, even covereing Re+RE time if installed at a shop. even some money to cover oil and antifreeze used in the swap. anyone else heard anything?? :?