from what i read in another thread, the Cree has a lot of light going Foreward, that will miss the great streamlight reflector, but the seul thing is more omnidirectional, so more of its light would hit the reflector first, as opposed to heading out the front unconcentrated.
conclusion, if you wanted to get the best SPOT from the streamlight , and also acting more like the luxeon did, it would be with the seul.
for some reason, LOTS of reflectors i have dont work so well with the cree, not to mention that stupid metal ring they put in there , but many OPTICS are working out quite good.
then out of the blue, a reflector you wouldnt think would work with cree at all, works perfectally.