Its shaping up to be such a nice battle in the world of R/C batteries. EP4600, IB4600, E-Power 4500, and perhaps even a sprinkle of the new Orion cells. Wohoo! Looks like all of these cells will have comparable runtime/voltage/IR. Wonder how the market will shape up?? One thing seems somewhat certain at this point though -- One brand will not dominate the market like IB has for the past two years.