Cells are rated at 1.2v, but non have that average voltage over a discharge curve. They start out at over 1.2v per cell, then drop down and average the number on the label. Then drop below that and down to .9v per cell. I've been told that 3700s are like running and extra cell in a 3300 pack. As in, more powerful, and runs for longer. It might not make a big difference in the first minute, but 3700s should be able to spank any 3300 pack at the 2-5 minute mark.