This is a kinda hard for me to explain as I know very little about how pipes are engineered..There are a few things though that I require before I call a pipe a good one.First of course it should not smoke hot.It should be light weight for the total amount of wood.How a pipe looks is important to me,but more important is how it feels in my hand.The weight of the pipe should be distributed evenly so that I hardly know I have it in my hand.I call this balance.Though I have some pipes with Vulcanite stems I prefer Lucite.If I get all of this in a pipe that I think is pretty it's a keeper.