[Serusers] SER for IMS

Hello I am in the process of evaluating a SIP stack for IMS enhancements (for CSCF). I compared SIPx, SER and reciprocate stacks for CSCF development. SER: Pros: 1. Can run as registrar/proxy/redirect server 2. TLS support for Security 3. Support for NAT 4. Web based management interface 5. IPv6 support Cons: 1. GPL license Resiprocate: Pros: 1. Slightly less distributed architecture than SIPx 2. Can run as registrar/proxy/redirect server 3. TLS support for Security 4. Support for NAT 5. Web based management interface 6. IPv6 support 7. Maximum standards compliance Many IMS headers are supported in latest release 1.0 SIPx: Pros: 1. Complete SIP based IP-PBX solution 2. Distributed architecture 3. Can run as registrar/proxy/redirect server 4. TLS support for Security 5. Support for NAT 6. Web based management interface Cons: 1. Missing IPv6 support 2. Large footprint I have following queries: 1. Can somebody point out if anything out of above is not correct or if people can add more? 2. Which stack is more actively being used for IMS enhancements? 3. Are there any plans for near future SER release with IMS support (CSCF mainly)? Regards, Gaurav Kansal