I have tried several of the silicon zip bags. Some of them can become impossible to seal, or need a lot of pressure to seal, which is hard on my fingers. I like these because they avoid that altogether. Sliding on the top works well and easily. One drawback to most of these silicon bags is that labels don't stick to them in the freezer very well, at least my sticky labels. Also, they are too floppy to go in the dishwasher, and unless very properly placed, end up in a heap, trapping water. So I w...