Just got my hands on the Ledbeam 3C and the SL 4AA propolymer luxeon. This picture was taken at 10 feet the Ledbeam is on the left. Both lights look equally bright and the beam is nice and round . The Ledbeam is running on 3 AA energizer alkalines with a AA to C adaptor.
If your LEDBeam is working properly and getting enough current, it should blow the doors off the the SL 4AA PP. That's how good the output of that light can be, since we already know that the SL is already a honker.