You could write a book from the lighter threads which have been in ETS thru the years.
My opinions are based on CUSTOMER SATISFACTION and REPAIR SERVICE history. My backwoods partner is a lighter repair tech. in addition to perhaps the most experienced outdoorsman I know. He carries:
1) DISPOSABLE Bic or Cricket FLINT.. not piezoelectric, butane lighters. Piezoelectric are significantly more vulnerable to dust and grit than flint. A wet Bic flint will dry! In severe cold, the lighters ride in a pocket near the body. At altitude, he's had no problems @ 12,000ft. BUT NOTE: All butane is NOT.. NOT.. alike. The cheaper brands absolutely contribute to problems. We always and only use COLIBRI brand for critical refillable butane lighers. But the stuff in the throw-away Bic or Cricketts seems o.k.
2) Zippo. Never a problem in cold, nor altitude. When wet.. it will dry. But we semi-waterproof with a bike tire inner tube "ranger band".. which is also a great tinder. You absolutely must refill at the start of each trip. No reliable way to keep fuel from evaporating over a week period. BUT, now Zippo makes a fuel cylinder which holds 2-3 refills which we pack along.
Guys.. there ain't a lighter brand sold in the U.S. which this guy hasn't sold or worked on. And there ain't an outdoor condition except being lost at sea that he hasn't muddled thru. I defer to the lighter repair guy!