NURBS or MESH on terrain build?

Hello.
What is better to work inside rhino? a Terrain Mesh or a NURB terrain surface?
I have testing this 2 surfaces. MESH result in better representation of the real terrain but is to complicated to Split, Trim, and fix some mesh faces. On the other side, NURB surfaces are more flexible, but more heavy and less inaccurate result from the original terrain model.

If some one could help and show me some tips on this matter.
Best Regards

I think you have summed it up pretty well… Generally we work with meshes and try to live with the problems/limitations…

–Mitch

Thanks for your reply.
I am struggling on split some meshes. The result is not the correct i need.
Can you please check this model on the RED curve inside the file?!
CPB - Terrain split help.3dm (19.0 MB)