piston questions
here's my .02 on it: if you use anything besides stock pistons a rebalance is mandatory.
maybe you don't *really* need it, but i'd rather spend that $325 to find out now rather than find out later.
LA and magnum's have different widths on small ends of the rods, the pistons have corresponding pin bosses. with machine work you can make them work but typically LA pistons on mag rods isn't the way to go. so those speed pros aren't the money saving gambit you think they may be.
depending on the set up, i'd probably be okay with a hyper piston. but if you're straying from stock a forged slug is the way to go. icon, dss and wiesco are all in the same-ish ball park. but if i was really going for it and building a bomb proof bottom end mahle powerpak would be my choice.
but as always, budget dictates a lot of choices...