I currently have 2 SIP providers. One hosts my home phone lines, and I am not disclosing that provider. However, with providing the SIP address, I will obviously be providing for the provider. In this regard, my home phone supports 2 accounts, and this account is intended to receive calls only. With that being said, if you wish to call via a SIP address, and not use SIP Broker, you can call sip:9531518@localphone.com.
Some SIP providers support setting SIP addresses as a speed dial. If this applies to you, and you would think you might call me on a regular basis, then I would recommend using that speed dial feature. Otherwise, you can call a PSTN telephone number I have, or my SIP Broker number. I can understand that SIP addresses are a little hard to deal with. Again, Localphone does not host any of my telephone numbers, so if something was to happen to that account, it is a matter of deleting this page.