I have no experience with the bags you speak of, but, I use a
"Foodsaver" vacuum sealer for small things.  Some items like underwear
and a bathing suit are vacuum sealed and just left in the Westy for when
they're needed.  I even have some of my spare parts vacuum sealed in
this manner (like a spare ECU, for example).  It sure keeps dust off and
keeps connectors from corroding.

Mike