iCharger 406 duo is the best charger ever made. It's been around for 4 years and still is the best charger you can buy. It is reliable, charges at 40 amps on two channels or 70 on one. You can do 40 amp discharge with a discharge. You can do up to 8 cell batteries. The 308 is 30 amp and the 4010 is 10 cell. The new X6 is small but only one port at 30 amps. Dislikes are no touchscreen. The price is worth it and it is a must-have for all stock racers.