I went for a long while without significant problems, so there was nothing to report.

Then I started getting occasional packet loss, then occasional complete drops. The drops became more and more frequent. After some investigative work to prove it wasn't my modem+router at fault (fair enough), AAisp looked at wider causes. They noticed that other a few other users connected to my exchange had experienced the same drops. They contacted the backhaul carrier and let them know, who fixed whatever problem the carrier had created in their earlier maintenance.

I was kept informed throughout, and David understood precisely what I was telling him without resorting to a "reboot your computer" script.
Their Constant Quality Monitoring graphs also meant I had a decent persistent timeline of failures and packet loss, so I knew when the line had dropped even if I was out.

Yes, they're a bit more expensive, but when my livelihood and much of my life depends on internet access, the money spent shows its worth during problems.