I think that a pipe is a pipe. Briar, cob, or meer - each genre has gems and dogs. The pipe is just a tool to burn tobacco, and they're not complicated: fill the end with the big hole full of tobacco, put the end with the little hole in your mouth, set the end with the big hole on fire, and imbibe the smoke through the end with the little hole. That being said, there are seven blends that I think smoke especially well in a cob - better than in any other type of pipe: Orlik Golden Slices, Erinmore, MacB Golden Extra, Samuel Gawith Grousemoor, Gawith & Hogarth Sam's Flake, Sir Walter Raleigh, and Granger.
My pipe mentor, my late uncle Danny, was well-known for his trademark MM cob and Granger (or Velvet when he couldn't get Granger). I remember when I got my first "good" pipe and tobacco, back in 1981, he just chuckled and commented that one day I'd come around to a cob and some Granger. 30-some years later, I understand just what he meant.