Got a chance to talk to a couple guys who climbed Everest on different occasions. One said he initially thought it was great but as the years went by after the climb he began to notice his memory was not what it was pre-climb and figured the time spent in oxygen debt while in the "death zone" did more damage to his brain than he would have liked and was concerned about future dementia issues as he got older.
The other told the tale of spending a night at the last camp before his summit push puking into a cook pot and spewing diarrhea from the other end, his butt sticking out the tent door while 60+ MPH winds lashed his naked tenders and a$$.
Now THAT sounded like fun!
