Ignition and Cirrus Link really do deserve much more credit, this combination has worked flawless for me for about 4 years now.
I'm in the Oil & Gas industry. I have several very remote locations that we communicate with using Cirrus Link Mqtt Sparkplug B protocol. Everyday (24 hours) these locations create more than 432,000 tag events and my Ignition server and Cirrus Link Mqtt modules has handled them without the first problem.
I think everyone should know this! (NOTE: This is all done on our own Cellular Private Network.)