Quoted By:
I want to like frame bags for their look, but I don't really see them as being practical.
The volume and weight you can carry on framebags before you turn your bike into a hobomobile is very low, a 20L backpack will equal the volume you can carry while allowing to carry bigger items.
I can see the advantages of frame bags in that the weight sits lower and most stuff is easily accessible while riding; except you bork you own access to your water bottles.
And once you put a backpack... why even have frame bags? Once you cross the treshold in which volume is better accommodated in a single, bigger bag, the whole point of the frame bag goes away.
Aside from all that rambling, you could use a backpack with those belt pouches, but then again I never owned one of these.