He's a very good engine builder by recommendation from the guy that did my heads. He has a top of the line digital balancer and assured me he was very pleased with how the balancing work came out. I'm using the stock rods which had the small end resized for the new pins that came with the piston set. I told him that the new pistons are supposedly lighter than the stock ones (I couldn't confirm that though as I didn't take him the stock pistons) He said that may be true but the weight calculations and the balancer don't lie. He said it was so close that he didn't have to use any heavy metal. Just the weight of the weld filler was sufficient. He actually welded the oem balance holes back in. I noticed your using aftermarket rods which may account for the difference between your setup and mine.