[gsich]

Yes, but only because of TCP and TLS connection overhead.

Once the connection is established, response time is similar to UDP.

[yjftsjthsd-h]

Does the connection get reused?

[cbsmith]

Yes.

[gsich]

Not for long.

[tracker1]

If the browser is controlling the resolver in question, there's no reason not to hold long-running connections, or reconnecting on disconnect.