The box should keep it for many months as long as you keep air from seeping back in.
To clear us from the trailer trash crowd, corked bottles are almost unheard of outside of the US. In australia and several european countries, boxes are de rigeur.
No spoilage, no contamination, easy to open, easy to store, easy to tap a glass, and the opened product lasts a long time.
Franzias "Vintners reserve" (a higher class than the usual) is a perfectly ok base pedestrian wine. Its as good as two buck chuck or most of the sub $5 a bottle wines you find at the grocery store. I can get it for ~$6 for a 5 liter box at the sams club up the street. Yep, thats about 80c per 750ml bottle. I've read some reviews and tried some different ones, and found that (oddly) the wines in 3L boxes are a step above the ones in 5L boxes. There are a couple of fru fru napa valley makers like black box that are offering wines equal to a $7-10 bottle at half that price. All of the tested australian wines (including CT's recommended and quite good hardys - in fact, try their port sometime) are quite good.
As we mused last year...the quality of "bulk wines", which were awful 10+ years ago...have simply closed the gap with the lower end "quality vintage" products.
In fact, theres nothing like taking a box of white wine out to the patio table for the evening to enjoy with dinner and an evening swim in the pool. Its got its own insulated cover, so it stays cold...
Note: the above behavior occasionally results in an infant showing up ~9 months later... (cough)...
In fact, a trip to
http://www.blackboxwines.com/ will tell you where they're sold. I just discoved that one of the local supermarket chains is carrying their stuff...excelllent...
(Gabe needs a brother or sister...