All the replacement heads are probably all the same castings. I would call promaxx and see what they do to them. They might be most likely to have quality work. I would be wondering if they do their own valve jobs in their replacement heads..
Thanks Cookietruck I figure there can't be too many different foundries making them. That's a good idea re the promaxx ones, might be a good deal if it's all quality usa finishing work on the castings.
