if i read it right then his question is whether it is ok to use large texture maps
with individual sculpted/baked normals and diffusemaps or if the engine ressources
quickly demand you to make use of tileable textures instead.
my opinion without knowing ue4-limits:
make use of tileable textures wherever you can as long the detail doesnt get
too low too much.
as a matter of fact i find it really hard to find documented information on the engines
capabilities, like:
ps4 / xbox one / pc
- max. recommended polycount
- max. recommended drawcalls
- performance decrease by texture sizes
etc.