I live alone and often find that salad greens and vegetables go bad before I can use them all. I've started using Ziploc Produce Bags, and that seems to help. I own a Foodsaver, and I've seen on some vacuum sealing sites that they recommend using vacuum-sealed containers or mason jars to store lettuce and other greens. I'm wondering which is better - a bag that allows 'breathing,' like the Ziplocs, or something airtight and vacuum sealed?