However, after some time of working with it, two important reasons surfaced not to adopt this technology.
-1- deRPC does not work very well
I had a number of issues in using deRPC:
-2- GWT deRPC is about to be depreacted by the Google GWT team
“DeRPC was created to help with large object graph serialization; however, DeRPC (NOT GWT-RPC) will likely be deprecated eventually in favor of RequestFactory.” (David Chandler on Google Groups)