Recently added both to my collection. There is not much of a comparison, The Surge has a large very nice hot spot, with good peripheral spill, even at it's tightest. The flood is very even. LOTS of lumens.
I bought the 3C SL because it was rated at twice the candle power of the 4AA Xenon SL. The 4AA has a wonderful beam, bright, and even, love the light. The 3C has a ringy, very small hot spot, not laser like, but tiny.It really does not appear to be brighter than the 4AA, except at the tiny center of the hot spot. There is a ringy slight peripheral spill (3C). Don't like it at all. The clip on the 3C is nice; works well for carry. The 3C has no flood.
Buy the Surge.