What do you want to know? Weather they accomplish their task or not? I'll be able to tell in time. One thing I am happy about is the head was INCREDIBLY EASY to pop back on the block with them. It will make a nice addition if the head has to come off and on in the car. It's lined up and done. You also get to torque them to 85'lbs instead of 65'lbs. No head bolt stretch like i experienced on the last engine either. I had to put washers on the old head bolts in order to get it to tighten down again.