When I had my first eye done they only did an 80% correction as at that time they did not correct astigmatism. Thought at the time it would be easier to correct for the astigmatism while also doing a 20% correction to achieve 20-20 with contacts or glasses. By the time I needed the second eye they corrected the astigmatism at the same time with a full 20-20 correction. Surprisingly the final outcome was I could easily see 20-20 for long distance and did not need reading glasses because of the 80% correction in one eye. That was over 20 years ago. Only recently have I started to need to use reading glasses in low light conditions. I will also add when I rode/ride my dirtbike/motorcycles and drive the RV, I have always wore my contact. I even raced SCCA & Legends for years with the single contact. Yup, one contact in the left eye the 80% eye. Now I will say I have heard of people who could not make the mental adjustment and were not happy. For me it was & has been GREAT!
rocmoc n AZ/Fld/Baja