ashdigger's response mirrors my Kaywoodie experience almost perfectly.
I found the early production, large ball, 4-hole stingers to perform the best, although sometimes the screw mechanism can leak, an unpleasant effect. The latter production 3-hole, smaller ball ones are rather lame and not worth buying. I concentrate on shopping for, and sometimes even buying, pre-1955 KWs
I have a Hyde Park billiard with push tenon and a stinger identical to the old KWs except that the large ball has NO holes. It smokes great, better than the KWs.
A corollary question might be "What is a stinger?". My old Parker has a metal tube which extends all the way through the airway. Good smoker, no issues, and I appreciate the cleaner airway and ease of cleaning. Conversely a Brebbia I have sports a similar tube but it is BAFFLED. Yes it works but is a pain in the butt to clean.
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