Talking to a SF rep, he said the incan's will be switched over to the led heads if they discontinue bulbs. This might be good or bad depending on which you prefer.
I have incan m6, m6lt, and xml2 md60. I prefer primaries for power and long term storage with no maintenance charging. The m6lt is the worklight with superior power. The m6 and mn21 is in dedicated standby ready to go on new cells and the md60 is ready to step in if I need two work lights or SF bulbs go out in any of my m3,4,6.
SF incan's are and will always be the muscle cars of flashlights. Led will surpass them, but you will still want to take them out for a spin.