Quick-Links are an efficient way to create connections inside a patch. They can send/receive any type of flows (data, audio, video, text, array, MIDI) and are more CPU friendly than wires or buses.
A Quick-Link is only visible to the main patch (including all its sub-patches), but it cannot be used to communicate between racks or different patches in a rack.
Unlike wires Quick-Links can be delayed by one calculation BLOC depending on the calculation order, not predictable.
For example, the following audio chain will introduce an additional latency of one calculation BLOC (generally 128 samples).
The solution is to use a + module like: allowed