Overlapping static meshes in level design and performance impact

I couldn’t really find information on this so forgive me if it has been addressed.

Once upon a time it was very very bad to over lap brushes in a map, which resulted in terrible long build times and map lag.

Since UE4 has gone in a different direction using static meshes in level design I have the following question.

To save time and effort I am wondering if I can over lap static meshes through out the map, putting them through walls and such without causing increased build time or lag in the maps when playing the game.
In the old days BSP Vis hated this and would make you pay for doing it that way.

Thank you for your in site, any detailed information would be greatly appreciated.

I see no problem in overlapping static meshes… the only thing i would pay attention to is z figting. This will casue bad looking flickering.

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