I use PowerLine adapters for connections between my network and my home entertainment system, and agree they're great. You get fantastic speed without running ethernet cables.
Just realize though... these PowerLine adapters only work when you have power to your house. They can't be powered by a UPS. So if you're relying on your Apex to notify you of a power outage, it's not going to happen using a PowerLine Adapter. Using an AC-powered wireless adapter, you can power it off a UPS, and assuming your modem/router is on a UPS you can receive notification of power outages and connect with your Apex during a power outage.