HSAs are the best kept secret.
Well, maybe not best kept secret, but I remember when I FIRE'd (before ACA), the missing piece of the puzzle was what to do for health insurance. That was my first introduction to HSAs and had me thinking, almost too good to be true. What's the catch? If there is any catch, I say to keep good records in case you have to show all the receipts of qualified medical expenses to the IRS. But, that's really not a catch as you should be keeping good records anyhow.
Have you ever seen a headstone with these words
"If only I had spent more time at work" ... from "Busy Man" sung by Billy Ray Cyrus