I have more cob pipes than briars.
If I remember right, there was a break in period for both types.
But afterwards, I can’t discern a noticeable difference in the tobacco flavors they impart.
Then the difference for me between the pipes comes down to draw and clench. And the cob pipes win this contest. My cob pipes are lighter, and perhaps most heretical of all, I like the plastic stems. The plastic stems have tooth marks that help the pipes settle into the preferred clenching position. Then when these stems finally wear out, I’ve already purchased a supply of replacements.
Sure I have a few forever stems, but they don’t clench as well. One of the forever stems is a P-Lip stem, and that helped me decide not to spend extra going full Peterson for this experience.
I don’t include esthetics in my comparison between cobs and briars. The occasional laudatory comments from my friends about my briars are pretty unimpactful and fleeting, they weight heavy on my mind not at all.