Other than one being permanent I don't believe there is any other difference.
It's like in a traditional stick car between pushing in the clutch pedal and moving the stick to neutral.
LOL, that'll do it. ;)
Ya, but a thief might have a more sensitive tool. Anyway, there is a guy on reddit that tests them for business reasons. He said they only reduce by a certain amount. 45 db or something. I forget.
I think you'll find there are still spots that aren't sealed completely. Doesn't make the bag useless, just a little less effective than it could be. Wrapping stuff in heavy tin foil can be effective as long as there aren't any cracks or seems.
The funny thing is, anything that opens isn't 100% effective. Any kind of gap or crack can allow leakage. I choose not to worry about it and do the best I can.