Dunhills were well made pipes and in the early part of the 20th century, were not only well made, but also quite creative in design and styling. Were they better than the other top English makers like Comoy, Barling, BBB, Charatan, or Sasieni? Nope. But they were well made and smoked well. While the wood was often unremarkable, the stem work was always exceptional. Add to this Dunhill's penchant for diverse stampings and arcane markings, the stuff that appeals to collector OCD. You could date a Dunhill. Some people study hieroglyphics and others study Dunhill.
The problem is that Dunhill's marketing sought to make the Dunhill more than a pipe. They sought to make a Dunhill pipe a symbol, the epitome of excellence, success, and financial status. And they charged a lot for the privilege. Dunhill may not have been the best pipe ever made, but it was the best KNOWN pipe ever made. And after the late 1960's, the quality became more variable as more pipe manufacture was outsourced. Not that Dunhill hadn't always outsourced, but as people became more aware of the unevenness of the product, the pricing and marketing really began to grate.
I own a dozen or so Dunhills, and they are OK, and a couple of them are really exceptional. I almost never think of smoking one, not since I started smoking Barlings. Dunhills are good pipes. They're not better than all other pipes and certainly, to me, not worth the money being asked.