New 20C MaxAmps Lipo 12000HV 2S3P 7.4V Pack

[GorillaMaxx360]

How good are these what kind of run times am i looking at on a maxx with 7xl, 125b and such. also how do i charge these on a 989 charger, do i need a balancer and if so were can i get one. Since the battery runtime is so long will it overheat the motor and or ESC the ESC will have ESC monster heat sink with fans, and the motor will also have a motor rcmonster heat sink. what do you guys think of these batteries.