These days, Dr. Grabows come with a filter but without the stinger mostly. The Kaywoodies still have a stinger, and they
are integral to the pipe by fastening the stem to the shank, so you can't take them off. I intentionally avoid stingers,
and only have the one on my Kaywoodie. I went to lengths to get a Parker without a stinger, since some of them still
have them. Some pipes promise you can easily remove them, like Yello Boles. As best I can tell, stingers were added
as a plus when pipe smoking was widely popular in the early 20th Century and on along, as a patented and/or advertised
feature, to make a pipe more competitive and to try to cement customer loyalty. I don't think they boast much appeal
anymore. Filters are somewhat in the same category, and are in the balance for popularity, apparently still standard among
some European pipe smokers. Another innovation that hangs on are "Systems" pipes, such as Petersons. Some pipe smokers
find these more trouble than they're worth in terms of keeping them clean. The best bet seems to be an unfiltered pipe without
a stinger, for most purposes, among most pipe smokers in the U.S.