Originally Posted by
acidfast7
also, I
don't like panniers are they're too mono-functional.
they're not comfortable for shopping or rock-climbing and not so good for an airline carry-on.
however, i will say that when I fly into southern Germany, I often see a tired Ortlieb or two used as a carry on.
Germans

When it is raining, it is a lot more convenient to carry panniers, than backpack with rain cover - for me at least. When shopping for lots of stuff, panniers give extra space in addition to backpack.
However, I too prefer backpack - most convenient when off the bike, or when riding off road aggressively.