I have compiled the Moodle Benchmark scores of MoodleBox 3.1.0 on Raspberry Pi 3B, 3B+ and 4B in to a single table. See http://www.syndrega.ch/blog/#benchmarking-moodlebox-on-different-raspberry-pi-models.
@kruse, I took the numbers for Pi 4B from your post https://discuss.moodlebox.net/d/112-moodlebox-3-1-0-poor-moodle-benchmark-score/6. But they are inferior to 3B(+). Could you recheck them? I wonder whether the two different MB releases 3.0.0 vs. 3.1.0 make a difference.
Did you use the very last version of Benchmark plugin? This last version fixed a nasty bug which rendered the measurement totally wrong in certain cases.
I suggest you add in your page the indication of the Benchmark plugin version used for each measurement.
Nicolas Yes, I've noticed in the other discussion https://discuss.moodlebox.net/d/112-moodlebox-3-1-0-poor-moodle-benchmark-score/1 that the Benchmark plug-in has changed. The plug-in version I used in both 3B and 3B+ is v1.3.0 (2019083101). It is the same SD card. Will add that information to the web page.