What are the advantages of using rockfill over earthfill to build road embankment?

With the use of rockfill to build embankment, it is not a concern regarding the build-up of pore water pressure during construction so that the embankment can be filled at the faster rate. Moreover, the use of rockfill
allows a steeper angle in forming road embankment when compared with earthfill so that it results in a small amount of fill. As such, it helps save the cost of construction. 

This question is taken from book named – A Self Learning Manual – Mastering Different Fields of Civil Engineering Works (VC-Q-A-Method) by Vincent T. H. CHU.