All prices are in US dollars.
Purchases can be cancelled for a full refund at any time within 60 days of purchase. After 60 days a partial refund for each full month of unused service will be provided on request.
From Arif, SIPSorcery user.
Primarily I use SIPSorcery to combine multiple VSPs [VoIP Service Providers] to manage calls at my locations.
The major advantage I see is the flexibilty to manage calls through dialplans.