Good, sturdy bags that seal well.
I'm kind of picky about freezer bags, after a few disastrous leaks in the refrigerator (oh, the joy of cleaning out three levels of a fridge because your marinade has made a break for it!) using store brands and even some of the name brands.  Since I started using the Presto bags I haven't even thought about buying anything else.  I now double all of my bags with marinade and liquid, because even really good bags aren't 100% all the time, but most of the time I don't find any leakage into the outer bag.
Rating: 5 stars