need to think warranty! Being a prescription lens, it's not going to be cheep so don't skimp on the frame. I like Maui Jim's. They have a two year warranty but if something happens to the nose pads or the side frames they will replace them for life. They also have a glass lens which is more resistance to salt scratches. That's a pretty good deal. The hinges are strong as well. I like the darker lens but even the darkest have a slightly lighter strip across the middle. This lets in more light right in front of your eye while blocking more across the top and bottom where you need it blocked. I'm on my third set and they last a long time.