I believe it is you who is missing the point.
No one buys a product just because it installs fast. It also need to give some value.
In the case of PortaSIP, with the limits stated earlier in this thread, not only it does not give value, it breaks important functionality that cab be achieved without it.
It is better (and cheaper) to use SER for SIP Proxy + Registrar and Cisco for b2bua + media proxy + media server.