"The high-speed CPU in the P305 smartphone offers superior processing speed that outperforms any 3G mobile phones in the market with 384Kbps downlink/uplink transfer rate. This translates into fluid and smooth video call on the P305, letting users fully enjoy talking and seeing each other."
As far as I know, all video calls on 3G networks are based on Circuit Switched calls with a bandwidth limit of 64Kbps. The standard is to use 3G Air interface (3G TS.26.112) for call setup, and use "ITU-T H.324M for multimedia conferencing over CS networks and [added] voice and video codecs with mandatory requirements for bit-error handling defined in optional ITU-T H.223 annexes."
I hope they are refering to the CPU speed helping the video call performance, not the bandwidth. If this is the case, then it would make sense, but the sentence is not clear for me.
The 384Kbps bandwidth available will not, or should not, impact in the video call performance of this, or any other 3G device - unless the standard in use is changed.
More information is available here: "3G-324M supports the real-time streaming of multimedia broadband wireless communications by routing traffic over the circuit switched network, instead of the IP network. Being circuit-switched based, the standard has all the hallmarks of a protocol ideal for streaming real-time multimedia, including a fixed delay, low overhead of codecs, and no IP/UDP/RTP header overheads".