Progressive Lenses vs Bifocals

This week I got new glasses. I've been wearing bifocals for 20 years, but finally decided to spend the money for "progressive lenses"--$340. With bifocals you were either looking close or looking long, a binary condition. With progressive lenses it's gradations. In either case you adjust by tilting your head to adjust the line of sight, which I hope will become automatic after awhile. Amazing what humans can get used to if they have to.