for those of us that got the DUO, it came with the 4 cell battery right?
Most likely. You can get it with either the two or four-cell battery these days. Back then I think the four cell was standard. It's easy to tell by looking at it.
I use the two cell on my helmet with the Duo because it is so light. It's the first time I have used a helmet mount with a battery light to mount on the helmet. It is really nice to not have wires going down to a pocket or pack. A heavy battery works but I always thought dealing with the cords was a pain.
I run the four-cell on the Olympia on the bars and mount the battery on the frame.
If riding by myself in a new area (like night riding on a Michigan trail I have never ridden) I throw the six-cell in my pack as my safety net. I have had to use it many times like when a battery that you thought was fully charged and it is not. Or that 1 hour ride turns into 3. No real need for a battery that big and bulky other than when we were running the Pitch Black races. But it's hard to beat as a safety net at that price. I also use it for backup when I have not had a chance to charge batteries between rides.
