You’ll need to use both.
To create the destruction meshes you would like you’ll need to use PhsyX Labs to create the different depth layers for damage. Then when you export. Import that apx file into UE4 where you can set it up and use it for it’s different destruction depths.
Unreal Engine 4 only has one Depth Layer which means you can really only get basic destruction. There are only two states for your mesh: Depth Layer 0 - Not Destroyed and Depth Layer 1 - Destroyed.
Using PhsyX Labs will allow you to have more control over your Destruction mesh by having multiple layers: Depth Layer 0 - No Destruction, Depth Layer 1 - Support Chunks, Depth 2 - Debris.
There really aren’t any better examples than the video tutorials that Nvidia provides at the moment. Once you get your destruction mesh created in PhsyX Labs and setup import that into your game and if you’re having trouble with getting UE4 to use it properly let me know and I will give you some tips. After setting it up correctly in PhsyX Labs there shouldn’t be that much to change in UE4 to get things to work together for some cool destruction! 
Tim