People like Ben Bicknell of the WA Barista Academy (he is/was? the WA representative of AASCA, organiser of the WA Barista championships...... (not to mention several of the staff of the WA Barista Acadamy have won state championships and placing highly in the National championship) emphasises using one way bags and squeezing out the air before resealing when delivering the professional barista course...... He also recommends that beans should also be emptied from the hopper back into the bag at COB each day.... and the air squeezed out.
Im sure he knows a thing or two about coffee, its preparation and storage!!