I see alot of good opinions here, if you look at my profile pic you will see the 400mah battery in black on the right (the shortest 3 of the bunch) and to theleft of them, you will see 2 blue 400 mah vision spinner vw. I highly recommend the vision spinners, however if you don't need the vw, the 400 mah shorter ones in black are literally half the price, and last quite a while. Those are my best recommendations, you can see the itaste 3.0 vv next to my zmax, much larger than all the 400 mah batts.