Some folks have reported that oxides in the valve can be avoided by keeping a layer of molten Boric Acid on the surface of the melt to keep the lead alloy from forming oxides in the first place.
Sometimes you get what you pay for, sometimes you only pay more for what you get.
Three shots are not a "group"...they are a "few".
If the Bible is the literal, infallible, unerring word of God...where are all those witches I am supposed to kill? (Exodus 22:18)