CapPack? Do I need it?

[BrianG]

It certainly won't hurt. Like Neil said, it will further reduce ripple currents which will reduce the stress on the ESC's components. I would say it is mandatory on heavier vehicles and/or if they are geared high. I wouldn't use it to compensate for mediocre batteries though.

The only downside is that the hookup spark will be larger, which will eat away at the connectors faster.