Paddleshift air tank questions

[whrdnsx]

I'm currently updating my paddle shift system.
Previously had a M800 & Geartronics GCU & Motec Air Tank Kit now updating to M150 GPRP.

The Geartronics GCU kit supplied a pressure regulator to fit to the Tank. Do i really need this? I notice there's no regulator on the Motec Kit.

Also is there any benefit to increasing the size of the air tank? or not necessary?

Thanks