I have a pair of L6's, and a separate KL6 being run on an M972 weapon light chassis instead of the turbo head. On a four cell body (actually designed for 2x18650's) on primary cells a KL6 pulls around 250mA, for incredible run time. I love them, but a good L5/KL5 does essentially the same job (but with shorter run time) and many find the more compact profile desireable.
IF you want an L6 or KL6, you better act fast and contact Mike at OpticsHQ while he still has a couple of them available. HTH.
Paladin
notes:
KL6 on 2x18650 tailcap current = 500mA
KL6 on 2x17500 tailcap current = 525mA
KL5 on 2x18650 tailcap current = 1200mA, yields ~ half the run time!