OP
A glued and screwed joint will hold better because the screws will extend the hold into the material rather than only the faces of the material glued together, which on mdf isnt too hard to break two glued piece apart...the first couple layers of mdf tear away from the bulk of the panel...but if screws were used, you would pretty much have to destroy the pieces to get them apart.just remember, its the glue that holds the box together.. Not the screws!!
Agreed //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gifthats kind of a no-brainer.. What I should have said is.. You dont need 400 screws in a 3ft^3 box to hold it together. A few will do!