One good thing is that they are unremarkable. They look like normal sunglasses. The other good thing is that they come with an extra battery in case the first one dies after an hour or so. Day at Epcot. Another disadvantage is that videos are no longer than three minutes. So if you record 18 minutes, you end up with six three-minute clips. Files are also saved in .avi format, a smaller file type that doesn't work well with Final Cut. The sound is also bad, often disappears. I try to return them but they ask me to spend $25 to ship them back to China. I dispute this with Revane.