These bags are the most durable I have found yet and I love them. My Irish Wolfhound puppy is 13 weeks old and 36 pounds - we use one bag each time usually. I know that for my breed of dog I will be stepping up to two or three bags used each time, but that is ok. Bigger bags would not help (if there are bigger ones out there?) - I can only get so much poop into my bagged hand at once anyway LOL!