My opinion, based on reading here and from both of these great pipe men being discussed is that there are no bad pipes. Well... except the ones that explode, catch on fire, break when you touch them, or are so ugly they burn your eyes.
As mentioned, a pipe is two holes in a material that burns at a greater temperature than the tobacco. All can be smoked if the smoker takes the time to figure out the way the pipe works best. Sure, not all pipes fit the way we prefer a pipe to work. I have my preferences, just as everyone else does. And, a good smoker fits our "way" of smoking, no more, no less.
Dunhills have a consistency. Dr Grabows do as well. There are people who will never find a Dunhill that fits their expectations. And, some people find excellence in every Grabow.
It's all subjective. When Rick Newcombe first started writing, no one in the US had ever heard of these Danish pipe makers. They were cheap artisan pipes, and he suggested we give them a try. Then, as a bi-product of his book, these cheap pipes started selling for thousands, because he had created a demand. He is accused of snobbery, but in fact he was offering something new for the thrifty pipe men. But...
Anyways, it's a pipe. The Native Americans used stone, wood, holes in the ground, whatever to burn this leaf. Then we used hot as hell clay for over a hundred years. The "worst" pipe on the market (or pipes deemed worst by smokers with preferences) is still way better than our options when Columbus landed.
Me, part of my enjoyment is the artisan pipes. But, I also enjoy learning how best to smoke my cheap beater pipes. So, do whatever floats your boat. I appreciate just reading stuff passionately written about the hobby. Heck, even conceded snobbish pipe smokers make me smile. It's all good.