Here is some info I found on a good blog post about the Safe Network Architecture:

Sitting on top of the hardware and network layers of the existing Internet infrastructure, the SAFE Network utilises the UDP transport protocol, with a Connected Reliable Udp eXchange (CRUX) sitting a layer above. The combination of these two layers, and the Routing layer above, provides the reliability and congestion control of TCP while also helping to deal with the tricky issue of NAT traversal.

Yeah in other more general articles, TCP offers error correction and UDP offers speed.