I bought mine at B and H, and it came in a Sigma original box with two batteries, each wrapped in a small polyethylene clear bag. The Sigma box had a camera compartment and an "everything else" compartment, containing battery charger, two batteries, two or three individually bagged camera to USBetc cables, a shoulder strap, and the paperwork consisting of manual, warranty card, and some other single sheet of paper. When you order from Sigma direct, you get the same as above. Sigma KNOWS that the battery life is p*ss-poor
and wisely supplies two batteries.
I will just determine the entrance pupil/ no-parallax point empirically, as I have done for other camera/lens combos. Yes, this is for panoramas. Google is my friend, here's Robert Tobler's empirically determined NPP:
"I determined the so called entrance pupil (i.e. the no-parallax point, incorrectly often called nodal point) of my Sigma DPx Merrill cameras for the hyper-focal setting at f/11. The entrance pupil of the DPx Merrills is different for different focus settings since the front lens of the cameras moves back and forth when focussing. I found the following values for the distance of the entrance pupil to the center of the tripod mounts:
DP1M: 38mm
DP2M: 32.5mm
DP3M: 37mm
The hyper-focal setting at f/11 of the DP1M and DP2M was computed for a very small circle of confusion (0.008mm, slightly more than the size of the diagonal of a pixel), in order to retain most of the sharpness of these cameras. On my camera an easy way to set these two cameras to this hyper-focal setting is to put the camera into manual focussing mode, and move the focus mark beneath the center of the left loop of the infinity sign.
The hyper-focal setting of the DP3M is even further towards infinity, but the movements of the front lens so close to infinity are very small, so the above entrance pupil figure works.
For near-field panoramas, larger offsets need to be used, as the front lens moves forward for smaller focus distances. (This is especially true for the DP3M!)"
http://www.dpreview.com/forums/thread/3530975