DIYLite - the CPF answer is to 'get both', as the definition of best dependo sn situation.
Q-III: Compact, small, decent throw. However, it uses relatively expensive batteries (CR123), has only on-off functionality, and the quality of the light depends on what batch of LuxIII's they got that day, which means that your runtime can vary.
2L LuxIII Tasklight: Has fairly good throw, and two-stage functionality. However, it's a lot bigger than the Q-III, the lens has reportedly scratched easily (IIRC), and some people don't like the low-high-off switch. I've also not seen it for less than $60 so far.
Another thing you may want to look at is the ElektroLumens XM-3 already mentioned in this thread, or Waion's sale on the B/S/T Lights forum.
(Edit: Took out 'Uses relatively cheap batteries (AAs)' on the SL TT 2L, as I had looked up the specs and some reviews referencing the Streamlight Luxeon 3AA light).