it's definitely better, and remember, moisture happens, even in the desert...rapidly cooling temps at night when the inside temp in the boxes will create condensation...and all it needs is a few minutes...the cotton fabric will absorb the moisture immediately...the moreso because the fabric is REALLY dry.... look around, isn't there something else you use only periodically that you could put out there and use that space for fabric storage in the house. It really isn't good for it. put your bed up a bit higher...they sell these 'can' looking things that boost it about six inches...then covered boxes could fit under the bed without losing any floorspace. If that is not practical and the garage is the only place you have, sure, the sheets will help...and ask all your friends to save the little humidity protection packets from their shoe boxes...sprinkle them all around the cabinet...they draw moisture to themselves so they get it first....