This is a hard space to get real reviews that are not either PR puff pieces or providers stuffing in shill reviews. Are you working with phones that support a

This is a hard space to get real reviews that are not either PR puff pieces or providers stuffing in shill reviews. Are you working with phones that support a real SIP stack or will this be taking existing analog/POTS phones and attaching adapters? Are you willing/interested in dealing with the setup and maintenance costs of running your own PBX via Asterix? Two that I have had relatively good experiences with are Nextiva and Vocalocity and I have heard reasonably good things about Packet8 (those subtle qualifiers you see there are because there is always something you can complain about for any particular VOIP provider -- no one has reached the level of being "great" yet.) Nextiva has decent virtual fax services and can support a real fax machine with an adapter, but my adapter just shipped yesterday so I can't yet say whether or not it works as advertised or how well it integrates into the rest of their vFax system.