I bought a GSG today, at Cabelas.
I was informed that the Sig OD version comes with at least one extra magazine, and a holster as well. Was approx $100 more for the Sig over the GSG at their retail price. However they price matched P-D's price of $315 for the GSG, so at $200 less than the Sig its an absolute no brainer.
I would have bought from P-D, but they only had the wood handle version, and I prefer the black handle. Normally I would shop P-D any day over Cabela's.