Breathers

[AJ_08]

Hello,
I currently have the stock setup: passenger side breather and drivers side fill cap. Which combination of upgrades is considered "better":
1. Keeping the stock drivers side fill cap and just replace the stock passenger side breather and cap the turbo inlet bell.
2. Replace the passenger side breather and cap turbo inlet bell, and add a breather to the drivers side oil fill.

Is it more beneficial to have breathers on both sides?

Thanks.