Many of my pipes are of the same shape as it's the one that I have come to enjoy the most, so I pretty much smoke every type of blend from the same shape. However, different pipes in the collection seem to favor a specific genre. Every pipe is a bit different even if it's the same shape, so I just try different things in each pipe I get until something sticks. Definitely not scientific, but it works.
I do have pipes of other shapes and have done the same experimentation with different blends until I find that one is better than another in a particular pipe.i have a well bent Bjarne that is aromatic all the way.
Cobs are pretty universal and handle all blends well. I have some for testing aromatics, one for Burley, and another for flakes. The flake one does especially well with Luxury Twist Flake and Hansom Flake. Dunno why, but that's the way it is!