Use these VoIP adapters already several weeks. It sets the information properly to, the call quality is excellent and the machine crashed never off. The device is easy ('m not a technology guru!) When all of the data from the operators - has at hand - in my case fairytel & voipbuster.
The interface offers endless configuration options, which naturally at first "terror" can one, but all so bad. Simply enter the SIP data, save, wait a moment and you're set.
Attention: Some routers (eg HUAWEI B593) must be the SIP port 5060 only unlock. In my UPC Gateway TC7200 I did not need that.
A very satisfactory purchase.