I cannot speak to the regs or flying re Lasix. I had it done at 45. In hind site, maybe for the wrong reason. I was always 20/15 as a youth, but it started to slowly deteriorate to maybe 20/30 mainly from astigmatism. I race boats, so salt and water don't work with glasses in a tough race, and I was told I couldn't wear contacts, so I did the surgery. Takes 10 minutes. A day of dark, a couple weeks of drops, and voila, 20/15 again. But there was a catch which I was warned about, that the surgery will accelerate ones need for reading glasses. I didn't need them them, or care, but now in my 50's I cannot read a newspaper indoors without reading glasses. So the docs will tell you, everyone will need reading glasses eventually anyway. But these procedures will accelerate that need. I also learned later that they have new contacts with weights that maintain orientation, so work with astigmatism, and that was an option.
So from a not military perspective, I would probably do it over again, but its not 'free'. From a military perspective, I had always thought that PRK was viewed as 'permanent' and Lasix was not, and therefore DQ. I guess that has changed now. What is true, is that in Lasix, the Cornea doesn't actually re-fuse. Its always pseudo attached. My docs at Hopkins who did it say they can re-lift the flap and redo it anytime with no new cut. That had always been the reason behind the military pilot DQ issue...that the flap never really re attaches, and could be dis attached easily.
So I will leave it to the Mil Docs re standards today, but there is some cost and there is some benefit.
My bias would be to do it, but push it back as long as possible. A close friend of mine who was an eye surgeon at Hopkins when I was considering options gave me two pieces of advice. She said "the surgery is trivial and almost anyone can do it. But get it done at Hopkins. If something goes wrong, which is remote, they can fix it. And don't do this stuff in your 20's or 30's unless you have to. Eyes change a lot during those ages."
So its worked out fine, and I am 20/20 15 years later, but reading glasses are a way of life now.