Sorry Mouse, just saw your post. I use a Razer Mamba. Only 1400 dpi, Polling Rate of 500Hz. In game sensitivity is down to 10% now. I used to be at 20%. I've been lowering it slowly over the past few weeks or month. I plan on lowering it still.
Because all mice are different, everyone uses different dpis, and in game sensitivities etc. The best way to find a standard to measure your sensitivity compared to others is to go in game, put your cursor on a feature (I use an edge or corner of a room) and do a 360 degree turn. Physically measure on your mouse pad the distance it took you to do the 360.
I just measured mine. It takes me just around 5.6inches almost 5 and 5/8ths to do a 360. I just recently discovered that a lot of 'Pro' bf4 players use a MUCH lower sensitivity. Closer to 20 inches or more to do a 360, which is why I've decided to start lowering mine more.