I can approximately 500 jars of food a year, and I use the reusable jars, mayonnaise, etc. Remember when Miracle Whip came in wide mouth glass jars. I saved every one of them, plus everyone else saved them too, and I use them all the time. I have never had any break, either in water bath canning or in a pressure canner. Of course, I break a jar or two every year, but most of them are name brand jars. You can'tenter them in fairs if they aren't name brand jars, but I have plenty of each, so I pick out name brand ones for my fair entries.