Those are also investment cast, which is a great way to get a quality product without breaking the budget. The only penalty is a few extra grams of weight, harmless for anything you'd be doing. IMHO they're also much safer to buy used, since steel lasts almost forever and can be rebuilt by the manufacturer if the rollers get sloppy. Sometimes you find an incomplete set for very cheap because he trashed 1 or 2 - but you only need 12!
