I have both the TLE-5 Luxeon and the TLE-5EX SSC. Both are very similar in physical appearance with thick PCBs that reduce the number of threads that hold the head on. The clear hemisphere over the luxeon emitter seems to be glass because it is very hard. However, the clear hemisphere over the Seoul emitter is a bit squishy, and feels like silicone or some equivalent. Keep this in mind if you have to wipe dust off of it. The reflectors that come with these seem similar, if not identical (I have not compared them side-by-side). The Seoul TLE-5EX is noticeably brighter than the TLE-5 and has a very nice, clean white tint; the TLE-5 luxeon is more rose colored in comparison (very very similar in color and output to my stock 2AA Mini MagLED). For my uses, the TLE-5EX transforms the minimag into a wonderful all-purpose light, especially coupled with NiMH batteries and the Terralux clickie. Avoid the bad quality NiteIze clickie tailcap.
If anyone has beamshots of the TLE-5EX Seoul VS. the TLE-5EX CREE, I would be extremely interested!