The Benelli M4 has a great set of ghost ring sights from the factory, but it's really hard to beat the near instant target acquisition you can achieve with a reflex/red-dot sight like the Trijicon SRO (SKU: SRO2-C-2500002). In order to install the new optic so the SRO and the ghost rings can be co-witnessed and used interchangeably, we had to remove the factory picatinny rail and replace it with a Scalarworks SYNC/01. You can install the SRO on the factory rail, but like you can see in the video, the optic will be elevated too far and will need to be removed in order to utilize the factory ghost rings.
Overall, it's a super easy install and looks/functions great as a combination. I probably had less than 10 minutes invested in the change overall.