Q2 - How do you choose a good outbound ITSP SIP trunk provid


Our customer base is in the emerging countries (India, Brazil, China). These customers make uni-directional calls to the US.
I had a question about how to choose the right VOIP ITSP outbound SIP trunk provider for my commercial VOIP application.

Our users use their softphones and make outbound calls through our Freeswitch server. We have our Freeswitch (similar to Asterisk) servers setup - one server is in Los Angeles, CA and the other is in New York City, NY. Users register with one or the other server dependent on which server is closest.

When shopping around for the ITSP provider, these providers sometimes provide me their gateway IP address so I can ping them. I assume that I should ping from my two servers to the gateway IP they provided (please correct me if I’m wrong), and that the provider with the shortest ping would be a better option.

I am unsure what are the important factors (above and beyond pricing) I should look at when deciding on which service provider to use.