You are asking the wrong hombre, muchacho. I'm not familiar enough with the language to recommend it but here's what my (grossly uniformed) opinion is: Go is literally designed for networking so I'd go with that. Rust is designed for performance so it can be good for scalability though and has some good crates for handling network connections (Though I'm just using std library for now).
If you a lowly high-level (heh, funny oxymoron) programmer like myself then Rust is a pretty fun option and has already REALLY helped me better understand concepts behind the languages I use day to day -- so that's fun! :D