I'm looking for a soft cooler about 24 can size. I want it to be soft so I can fold it down when not in use. No hard liner inside a soft cooler, that won't work for me. I know the soft sides don't keep things as cold as a hard side. In general I just need cooling for a few hours. I've heard that Polar Bear and Norchill are the best. Has anyone had any experience with these? Any other brands?