I learned my lesson after stumbling through the darkness on the PCT.
Carry 2 headlamps.
I left Mt. Katahdin with a Black Diamond Spot and a Princeton Tec Fuel.
Walking into Monson in a thunderstorm the Princeten Tec sputtered and died.
Despite being rated as waterproof. Despite me drying it and replacing the batteries it never worked again. Major bummer.
The Black Diamond Spot alone got me to Pinkham Notch, NH where I scanned their rack of headlamps (not many options). I finally chose a Princeton Tec Vizz because it was supposed to be completely waterproof and VERY bright.
It was indeed waterproof and very bright. However, it was also very heavy. It burned through batteries much faster than the advertised burn time. The multi-modes stopped working a week or so down the trail. By mid-Virginia the casing had cracked (despite me babying my headlamps) meaning I could no longer wear it.
Obviously, I didn't have time to find a PO and mail the broken one with an explanatory note to the company. So, I threw it out. When I got home and sent them a message explaining the situation: why I was dissatisfied and the reason for the delay in contacting them. I didn't ask for reimbursement or replacement.
I received a reply that in short said, "Too bad." That response irritated me more than two failed headlamps in two months. Companies that don't care about their customers enough to offer more than a form letter condolence do not get my business. The email closed with, "Next time, send us the broken one and we'll replace it." Sorry, but there won't be a next time, Princeton Tec. Your headlamps don't last and I certainly wasn't pleased with your customer service.
On the other hand, my Black Diamond Spot worked perfectly throughout the hike. It didn't gobble batteries like an insatiable dragon. The modes worked. The case didn't break under normal use. It didn't short out in a rainstorm. I can't comment on their customer service because this headlamp is so awesome I haven't needed it.
So there you go. The Tale of Two Headlamps (well, technically 3). I 100% recommend the Black Diamond Spot (or it's big brother the Storm which Adam uses). Princeton Tec? No way.