I like the Decatur pipe knife, all business and looks like it would last forever. A few of us don't ream ever, but scoop out the bowl then wipe it out with a paper towel or napkin that's a little abrasive. This maintains a thin carbon layer but no cake per se, and the full width of the chamber. This pipe knife would provide a thorough scooping for the purpose, though a pipe nail does well too. I have pipes that I've kept this way for thirty or forty years, and it really preserves the briar.