Performance - Skeletal Mesh vs. many components

i am currently trying to bring a robot which was created in CAD into Unreal.
The robot is on wheels and can extend its upper part.
I created a hierarchy in Blender with empties (aka dummies or nulls) and linked the relevant robot object to this hierarchy.
Then I exported to fbx and imported to Unreal by “file -> import into level”
This got me a blueprint of the robot with the hierarchy intact.
Then I rigged it with Blueprints so that the player can extend the uper part and things like that.

Now, since it is a CAD model it consists of very many objects, around 650 at this stage. This of course costs performance.

My question is, would it be better to simply join these objects where possible and go the route I have gone or would it be better performance wise to create a skeletal mesh and re-rig it?