Routers are also a great way to fill walls of barrels.
It also gives you more barrels to place, as you don't need to alternate pipe (or tubes) and barrels.
But they can make it a little hard for you if you don't set them up properly.
Pretty much this. tubes and a filter are cheap early on and easy to setup/understand.I use pneumatic, just put a single item in the barrel first to control how it is used. I usually set up a "market" of a type, barrel, pnu, barrel pnu (as the only load from the top). I block them out by content (food, bricks, ores, etc)...
Cheaper as it is difficult to get things out of barrels....I just do not waste my time any other way until I work up to managers to replace the system.