First, in case you haven’t seen this, the table here compares OS/OSPi/OSBo:
https://opensprinkler.com/faq/#technical
– You are right that all of them run the same firmware, the OpenSprinkler Unified Firmware.
– To make them all compatible, if we release cloud support, it will also be available on all three products.
– The plugins are only available for OSPi/OSBo by running Dan’s Python-based Firmware. It is not part of the Unified Firmware.
We only recommend OSPi for users who have experience with RPi and have knowledge about Linux. The reason is that unlike OS, OSPi is not a fully assembled product — you will need to provide RPi and burn SD card yourself. No matter how easy the set up process is, you will eventually encounter something that requires technical skills. So if you have no experience with RPi or Linux in general, we would recommend OS instead.