I have had about 8 ARC LS seconds,some were a bit dimmer than average, but still usefull, a couple had greenish Luxeons, a couple were perfect except for anodizing defects or epoxy smudges, and one had obviously slipped in a vise when something was tightened leaving gouges in the head (that one was the brightest of all). All of them were quite useable and except for a couple I traded, I still have and use most of them.
I find all models of the LS usefull and even the rev. 0.9/rev. 1.0 models have some advantages in terms of alkaline battery life and being able to use a single AA. So no matter what you get it should be a decent light. On the other hand, if a "grab bag" is not to your taste, a first quality Micra is only $20 more.
Or you could just get both. :-)