Sorry just saw this. The easy answer is you can mix and match cards in the SD slots. 64 in A, 32 in B, etc. As far as recording time, it will depend on the card size, as you probably knew, but also the quality setting (FXP, MXP, etc). Here is the cha...
I shoot in low light all the time. I set the camera to Aperture Priority and go from there. Bring down as low as needed, I set it to 2.8. I shoot 1080, 60i but if you are still getting noise you can go to 30fps to let in more light. I shoot at clubs ...
