As for breakin in, the V2s just have so much less comm wear you don't need to nurse the break-in that much. If you do the run-in without having the motor on the car it will take forever. You want to put the motor on the car and do a few easy runs on it. Peak power comes after a few runs, don't put a new set of brushes for the mains hehehe...
Usually you want to check the comm every now and then, you probably will cut the comm a little one or two times before you actually need to change the brushes.
The new Edge brushes have the copper shunt wire for the enduro and the silver shunt wire for the sprint. They are narrower (flat sides and same height as before) and give a little more power, compounds are slightly different too.