Having now played with OpenHabian on a Raspberry Pi 3 for a month or two, I'm ready to make some statements to the build and quality of the software architecture.

OpenHabian

Originally I was more impressed with the flat config structure (json) and and adoption of linux file and folder best practices of OpenHabian. Having used the system for a month or two, I began getting into extending the programming and the annoying use of Java in the underlying structure was frustrating. Json syntax was finicky and prone to producing weird effects when written by my poor keyboarding (damned trailing spaces after commas). That problem was highly mitigated by the fantastic effort of the OpenHabian team to provide custom syntax highlighting in terminal text editors like nano and vim. Web based panels are supported by oldschool, flat, ".items" that represent actions and ".things" representing physical-ish things items can work against. It was an elegant, ssh+nano heavy, solution based on, I assume, legacy OpenHab 1.0. A definite negative of the current situation is this mishmash of web based solutions/panels/sitemaps and the old .items text files. I never found the db that web-based discovery kept values. It could also hide items and things in there, when they should autogenerate .items. I'm not sure I'd ever have enough household complexity to really benefit from a relational database storing my values.

Zigbee serial shield - OpenHab keeps losing it's relationship with devices when our shitty Telus provided router craps put. Third time, I decided to move back to Hassbian. We'll see how that goes.