ITSP IAX Trunking (or SIP) Reviews & Best Deals?

I’ve seen a couple users here recommend Split Infinity as a ITSP, but most just point to the VoIP Services Provider Wiki. Can anyone recommend such a provider? I really am trying to determine what companies are reliable and good deals, so I thought this would be a good place to check. From what I read, IAX would provide lower bandwidth requirements/call, so it would be helpful to use IAX over SIP. I need at least one 812 (Bloomington) area phone number, and currently expect to need about 5 simultaneous calls for my small business. I would like the ability to call anywhere in the world through the provider, though the vast majority of calls will be in the USA. Thoughts? So many of you have been helpful while we are exploring the world of Asterisk and non-Vonage VoIP. Thanks so much!