Unless the vast majority of the food you take (by volume) needs to be refrigerated, I'd say the BWJ insulated system is overkill.

I bring fresh steaks and quite a few other items that benefit from being frozen to start a trip.  One small soft-sided cooler holds plenty for a party of 4:

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(The above is not my ad, it just shows the cooler I use)

REI and Cabelas have similar products.  If you need more than one, get two.  You can supplement the coolers with Sterilite or similar plastic boxes to hold your non-perishable foods.  For a party of four, I use 3 sterilite boxes that stack in my pack plus the soft cooler for frozen items.  I pull items out of the "freezer" as needed in time for them to thaw.  I can keep foods frozen for 2-3 days and refrigerated for at least a couple days past that.

I've had to give steaks time to thaw even on day #3 of a trip after pulling them from the cooler in late June...they were still soft-frozen in the middle.  Your mileage may vary depending on air temperature and how much sun-exposure your food pack gets.  

I get maximum benefit by packing the cooler pre-trip and putting it in my freezer at home (left open to allow max cold penetration) until the moment I'm ready to leave, then zip it up tight and throw it in an ice chest for the drive up to the park.  If the  cooler is stuffed full of frozen food there's no need for ice.  The food *is* the ice. Put the least perishable items (or items to be used first) around the edges and the most perishable items (or items to be used last) in the center.

This works well for me and I'd hazard a guess that it weighs a few pounds less when empty than Stu's massive insulated box.