Well, here is my 2 cents. For biking I had a pair of bifocals made specifically for bicycling. I measured the distance between my Head and my Garmin when I was riding and also paid attention to where the Garmin is in my field of vision so I could place the near part in the correct place. When I need sunglasses I just use polarized clipons over my glasses. They work quite well and are a lot less expensive than having to buy a pair of prescription sunglasses. I've never been an fan of progressive lenses especially for riding a bicycle. I got the bifocals for when I was touring so I could read the Garmin map easily. I don't really need them to read the cycle computer.