Most of the info needed is in the Directly connecting to Optical Pulse Counter with RPi? and Pulse monitoring on a Pi threads.
If you hook up the pulsecounter to the emonPi rj45 and all is well, that is indeed the simpler option. If you find you need or want different debounce or any other changes, the Python to emonHub solution makes it easier to make changes and also retain those changes when updating via emoncms.