If the 2b credentials is used in the OBi device, after installation, you may use it as an ordinary corded phone. It means that you may have call waiting and call conference, as a result, you have a maximum of two lines.
The quality is almost the same that I am not able to distinguish either of them.
Also I am able to use to my Asterisk server to make two calls almost at the same time to make two calls to the US via the same GV account installed in SP1 of OBi110 without any problems encountered.