I have not used it with more than 30 devices at once, however, based on the linked Apple document, I take it to mean that only 30 can be connected at once. Then you could potentially hook up 30 more, and then 30 more, if you like. But only 30 USB devices can be connected at once.
Page 2: "...up to 30 USB-connected devices at the same time."
Thanks. I know the Apple document says that but I had heard that it was not a limitation of the software but just that they had tested it on 30, perhaps with their cart. I saw a tweet from someone who had used Configurator with a 32-iPad cart and said it worked fine. There is a 49-port USB hub I saw that would be perfect for our tech center. If I could connect 49 at a time, it would really speed things up.
depending on the complexity and the burn time, sometimes more devices doesnt mean more efficient.
If you are doing a 45 device deployment, and the mean time between start and finish per single device is 3 minutes, it doesnt make sense to line them all up, connect and press play.
once you get your settings straight, press play and the tool will do devices in parallel asynchronously. when one finishes, unplug it and plug in the next device in the set.
Don't do it. That is my advice and I have done it more times than I care to admit. I have 60 iPads in two carts and if you hook both carts to the Mac that is running Configurator, it LOOKS like it's going to work but it doesn't. You get one of several different error messages, the most common being "Cannot restore from backup". Then maybe half of the iPads end up with the white screens where you have to choose your WiFi, connect to the cloud, etc. and Configurator alone can't get them out of that state. You have to find the ones with the white screens and make all the choices even though you already made them in Configurator.
Maybe typing this will make me remember it. Configurator is not fast or easy to use, but it's WAY easier if you don't hook up more than 30 iPads and it is also easier than using iTunes and more free than any other MDM solution.
You can definitely manage more than 30 iPads with Configurator, including different settings and everything, but I suspect that you know that.