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xkcd #2929: Good and Bad Ideas
(imgs.xkcd.com)
Alt text:
While it seemed like a fun prank at the time, I realize my prank fire extinguishers full of leaded gasoline were a mistake.
So the scenario is A) you have transitions that work 90% of the time and a pair of prescription sunglasses for the times they don't Or B) you have regular glasses, and still have prescription sunglasses.
Option a means 90% of the time you don't need to carry an additional pair of glasses with you.
I used transition lenses for a decade, they are great.