I wouldn't waste the extra money on them, plus forged pistons take forever to warm up or they slap like crazy. The stock 6-bolt internals are good to over 500hp. You also don't need a whole set of 4 pistons, just 2. And while you're doing them, you might as well re-ring pistons 1 & 4 too, hone the cylinders, and be good to go for a long time.