It might well be the knife-enthusiast equivalent of “Glock vs. 1911” but most people seem to have a pretty distinct preference. In general, I am a tip up guy. For right pocket carry, tip up presses the blade into the back seam of the pocket preventing accidental opening.
Tip up also has the advantage of putting your thumb right over the opening stud or “Spyderco Circle”. For flippers the index finger is likewise by the flip tab. At the moment, the Benchmade Mini-Grip, Byrd Meadowlark, CRKT Hootenanny and Gerber Propel are all tip up folders in my EDC rotation.
The one knife that I carry (well, when I haven’t misplaced it) that is tip down is the Leek. There are two reasons for this. First, for a smaller knife, I find that gravity pivots the knife to align the tab more naturally with my finger than on a larger flipper like Hootenanny. Aside from that, when you reverse the clip on a Leek, it leaves the framelock exposed in a most non-aesthetically pleasing way.
What is your carry preference, tip up or tip down? Why?