I finally got to field test my upgraded StenLight this week with 5 full days of TAG caving. John Harman and I compared it to his new
Serv-Light in
Cemetery Pit's big room, and the premium StenLight
killed the Serv-Light in distance and spot brightness; the Serv-Light does indeed have a beautiful, wide and smooth flood, while the Sten has a very discrete flood ring and center spot, but the side-by-side comparison in illuminating far-away features easily went to the StenLight. In fact, I had to continually turn
down my StenLight when shooting photos and video because it was
too bright for my camera. The upgraded Sten really is like having every setting turned up one notch, and having a new crazy-bright turbo setting. If you cave in big cave, this means more light; if you cave in "mortal" cave, this means much longer battery runtime. If you stare at a survey book for hours-on-end, "low" may not be low enough without sunglasses.
For what it's worth, I caved all week on a single battery charge, but I'm not able to make any claim as to how many actual hours use it was, or how much relative charge was left over - I'll just say that it's nice to not have to even give it thought while on a caving trip!
In addition to upgrading the LEDs, the new premium Sten has a field-replaceable cable (which requires disassembling the back of the lamp with an allen wrench to swap it out) which finally has gold (plated?) pins. I've had continual problems with the connector on my lamp over its three years of heavy use, due to corrosion and mechanical issues with the male and female connectors. While I applaud StenSat for finally going with a corrosion-free pin on the lamp-side, I've already had the "tip" of a new pin get bent, requiring an in-cave fix with a knife to fix. In my opinion, this style connector is just not suited to cave use, and I'll soon be replacing these on my lamp with
Deans Ultra plugs. The field-replaceable cable, however, is excellent insurance against a connector or cable short ruining a long cave trip; I keep a replacement and an allen wrench stuffed into my "space blanket kit" at the bottom of my pack.
The upgrade procedure went very smoothly. I purchased the premium upgrade from OnRope 1's website in December 2008, shipped my headlamp to David Niemi at StenSat (who has continually provided me with superb technical support for as long as I've owned my Sten), and it was shipped back to my house in just about one week. Note that
my StenLight is a very early model and has aftermarket (JSBurley) reflectors, not the stock or upgraded-stock optics. Vanilla "premium" StenLight may give slightly different results, YMMV.
So, is this upgrade worth $90? Do you cave in borehole, big rooms, or tall domes? Does your definition of "long trip" mean that you won't be sleeping in your own bed tonight? Can you
ever have enough light underground? My personal answer is that this upgrade is significant enough that $90 is a
bargain for more light, longer runtime, and less chance of primary light failure.