4 climbers, 4 headlamps on a multi-pitch trad route...the zoom out shined them all. Bulky, heavy...yeah...so is a work horse. If I'm carrying a headlamp 'cause I might get caught on a climb in the dark, it's LED, if I know I'll be in the dark, it's the zoom, halogen is hard to beat. The Petzl Duo is the best of both, but you're stuck with the bulk and weight when you don't need it and they cost twice as much. The zoom isn't the only head lamp I'd own, but for route finding, on the rock or on the trail, I want at least one person in the party to have halogen. I've had a zoom since it was the only one to own and I'll be using mine from time to time for years to come.
This is an old-technology headlamp that has seen its day and that day is gone. At one time this was the light to climb at night with but no more. Use your money to buy a nice LED headlamp with at least one 3-watt LED and you will be happy with your purchase.
If you are really set on an antique, buy a real one like a coal-oil lantern.