Buildcraft pipe AI has been improved- so a full inventory wont result in dropped items.
Barrels (Factorization) only hold 1 item type (but a lot of it), so a row of barrels with a pipe across the top will auto sort for you.
The diamond pipe will split off items types placed in their respective colour channels in the pipe's GUI- so junk goes to the barrels and ores/gems elsewhere. Pipe routing at a junction is still based on chance, so 50% of the materials will loop around and go back through. Just watch out for entity lag if all the barrels fill.
Diamond pipe sorting is very basic and fragile- one foul click and you have to reprogramme the pipe.