I have been doing some research on getting larger mAh 3S LiPo battery for my build and was looking at essentially the same size battery. I currently use 3S 1P 4000mAh 25/35C Zippy Compact batteries. Staying with the Zippy Compacts there was a 3S 1P 6000mAh 25/35C battery that was ~150grams lighter than two 4000mAh batteries in parallel..... I purchased a parallel connector.
My build was ~ 2100grams AUW before the just added gimbal (which I am still working on).
I am afraid to get higher "C rated" LiPo's as I believe the higher rates of discharge would fry my cheap power distribution board.
with my 40A ESC's and 3542 size 1450kV motors. I also believe that a lower kV motor and larger props with my current setup would fry my PDB.
I hope my rambling is useful.