A customer has a R3 BCM50 and we are looking to provide hosted IP or SIP trunks to replace the ISDN2s. As we cannot provide SIP even if we upgrade him to R6, I am looking to supply a SIP to BRI gateway. Does anyone have experience with Mediatrix, Patten or Sangoma gateways, who would be willing to share a config file or attend site with me? (UK based)