Ok @nachocodoner I seem to have managed to fix the issue with large memory usage in production. Looks really good now both client and server side.
Up until 3.3 it was not possible to cache split code via a CDN because thouse were fetched with a POST call.
With 3.4 … SURPRISE 
“Hit from cloudfront.”
It is now fine to throw those massive libraries in the main bundle and split the code and not worry that your Node server turns into a file server.
I am really happy with where we are now.
