I have been using the plus model (no pvc) for 5+ yrs, they are great. I do prefer the 'front' to the rear because it's easier to use the straps to tie them down and make them less floppy. I also prefer the plus model to the classic, they just fold and fold and refold, no wear and tear from refolding over years and years (and no toxic pvc; I know the toxicity is confined to the manufacture area, not really an issue to stuffing my lunch into these things on a daily basis).