I have yes. That was the original manner I had them connected. Ie: Internet gateway / Router > Melco Switch > CX > EX. It was easy enough to experiment, and when I did connect both the CX and EX to the Melco Switch there was no going back, especially once I got my hands on an S60 to power the Melco switch. What improved upon that was using SFP instead of Ethernet between the ISP modem / router and the Melco switch. I went with a Sonore Optical Module Deluxe and Finisar SFP single mode modules. I stream a lot from Qobuz and wanted the best quality streaming possible.
I believe there are a few threads on this forum about adding switches into the mix. I think this is the one that has a lot of interesting insights: Audiophile network switches