The QU16 is well endowed in the mix-bus department, and in addition to the main left/right FOH mix there are 10 other output buses and two dedicated effects buses. Because six of the mix buses are stereo and therefore only require one fader per pair, there are enough physical faders to control the line inputs, effects returns and mix buses all within the second layer, and so once again everything is kept simple and neat. And of course, the master fader is separate and therefore always available, no matter what the other 16 faders are controlling.
A row of buttons down the right-hand side selects the various bus mixes, and brings up each mix in a 'sends on faders' configuration, where the LR master fader becomes the mix fader and the mix inputs are all on the other two fader layers. This is by far the quickest and easiest way to manage the mix buses, whatever they are being used for, but the mix sends can also be controlled on a per-channel basis by using the channel mix sends screen, where pre/post settings can also be chosen. For a basic stereo main mix with a few auxiliary sends, nothing needs to be patched and you can be up and running in literally under a minute, but as ever there are more options available if needed.
Metering is arguably more important on a digital mixer, as the surface can at any one time be operating in more than one mode, and the QU16 provides a simple three-way LED indicator on each channel to show signal detection, signal at a 'good' working level and peak warning — a simple but effective green-green-red system. The main output meters (also used for P/AFL settings) are nice, bright 12-segment ladders and all metering is reflected on the appropriate screen display. There's also an overall meter view screen, which shows all the inputs and mix levels together; I noted that the display shows channels 1-16 at the top with the stereo inputs and mix buses underneath, which is the other way round to the actual surface layout.
As a live sound mixer the QU16 is about as easy to use as it gets, and the provision of a dedicated talkback mic input (with phantom power) means that you don't have to tie up a local input, which is sometimes the case with compact desks. The talkback is of the press-and-hold type, and while it doesn't have a dedicated surface control for level, this can be set within the relevant screen using the encoder.