Haven’t ever used one. I’ve worked on all sorts of consoles over the years, from the big SSL and Neve desks all the way down to the small Soundcraft and Mackie mixers.
On the digital side, many churches install the Behringer X32 console. Decent board, easy to navigate.
I have only just started seeing the GLD-80 in churches. It is being used in the church I attend down in Florida and at the church I attend in Canada. I don’t have any data points to determine the relative popularity of the GLD over the X32 consoles in churches so it could well be that I haven’t been attending the right churches!
I’ll get to work with it in early July for a week.
To get familiar with the console, I downloaded the GLD editor, a software app that mimics the functionality of the board very closely.
Aside from the routing, which would vary considerably from site to site, the basics are conceptually similar to most any digital console. The workflow looks pretty straightforward as well. The installation uses an L-C-R system design, not all that common in live sound, and that will be a fun environment in which to mix.