I swim laps for an hour per visit. A few weeks ago, I forgot to take my Magic 5 goggles with me to the aquatic center. I have a backup pair that are not made by Magic 5. I put the goggles on, started to swim, and the goggles leaked! I had to stop, dry out the inside of the goggles, and put them back on. It happened again, and repeatedly four more times. I spent at least a quarter of my alloted time readjusting the goggles. The following day I remembered my Magic 5 goggles! Put them on without a second thought. I swam laps the whole hour without interruption. The goggles just fit, no leaks, and no anxiety over getting the goggles adjusted properly to fit without leaks!