First, I of course bought a couple of spares while they were on sale because I too like the durability of the little light for situations where I would not want to ding up a machined aluminum Luxeon light, and it just makes good light in a nice beam shape.
It does put out a significantly higher intensity with the 3 D cells, I am sure due to the lower internal resistance of the large cells. As far as that goes, I am hoping the Luxeon is up to the job based on my comparison to the StreamLight Propoly 4AA and the Dorcy 3-D lights I have. Both use a 1W Luxeon and put out at least as much overall light as the Craftsman bulb in the 3-D Mag.
My only other concern was at that output level if the PR base could dissapate the heat fast enough. It is nowhere near as bad as a 3W for heat, and running with the reflector off, I can touch the metal bulb holder without burning myself, but it would cause pain to hold in firm for an extended period. The other comparison for this would be the Everled, which is a Luxeon in PR base, but I don't have one (yet:naughty: ), so I don't know if it really compares to the output of the Craftsman bulb.
So that is all very subjective, and in the end for me it is an ongoing $13 experiment which is going very well so far. BTW, Sears sells a 3-D light with the same sort of bulb, for all I can tell the same exact bulb. I was not going to drop $30 on that one just to see if it was the same output, though. It could be possible that they use a higher resistance in the bulb base to throttle it down for the D-cells. Anyone have both?