Originally Posted by azscoob
My thoughts on the stainless head is simply that stainless is harder to strip out if it needs to be dismantled, and warpage should be non existent, not that it is much of an issue in the composite head from what I understand.
Not only is it better for re-threading, but it will take a direct hit much better than the plastic ones (believe me I know). I tend to think that with the plastic heads that they are being stressed with a metal pipe fitting on them and getting smacked just right will snap it off.
I have not seen any difference in performance between the two (speaking of the heads only as all my pumps are March).