We bought a couple for a weld job this winter and I really liked em. They auto darken just as fast as the surface ones do. They are powered by the light off of the arc so no battery changing necessary. It was nice to not have to flip up the weld lens all the time. I just wish they would make a 4"x4" one for the newer kmb weld lens holders that cover your wh*** faceplate. (I just blacked out the rest of the cover lens with elect tape) One other drawback is they darken to about a #9 and you cannot adjust that but #9 works pretty well for welding mild and stainless rod (which seems a bit brighter). I haven't tried one for any kind of cutting or gouging though. Hope this helps.
That's a good tip. I was thinking about building a housing and mounting a regular surface type inside it. How about batteries? None? Just solar powered? what is the range of darkness? and can they be removed fairly easy. Ive had my surface hood go black and now lightnen up. That would suck if you couldn't remove it or move it out of your way. Let me know how much that was. I imagine you could add a flip cover on that with an additional light shade while burning right? I cant imagine why they, who built the one you bought didn't figure on using the lens for burning too, sounds half assed like most tools we use. Seems like there's always a tweek factor involved in every thing you buy. Dale