Landline gone? You don't need the spa3102. Asterisk and your internet connection is all you need to have broadvoice working.
That's true. But after Broadvoice was working, I needed a way to actually call and talk to people. I could...
1. Plug a headset and microphone into the back of my orbiter and use the softphone. (cheap, but inconvenient)
2. Connect a VOIP phone directly to my LAN. (expensive)
3. Connect an Analog Telephone Adapter to my LAN in order to provide an FXS port for my existing analog phones. (convenient and inexpensive)
I chose option three. Of course, the SPA3102 is overkill with a lot of capability I don't use, but I did need some sort of ATA