Overhead of Realtiem GI with no realtime with indirect lighting

Hi,
I want Realtime GI turned on for our game, only for the weapon selection lobby, its inside a shipment container lit with realtime lighting. When you spawn into the world (Multiplayer game) there is really no need for Realtime GI since the world is baked. Only realtime lights we have inworld is muzzle effect from weapons. If I set the bounce intensity to zero for these lights will it create the same performance impact as turning off reamtime GI all together? We also have a mixed mode dir.light btw.

Thanks