OS is a very good system, very flexible usage. I use 6 of these currently for commercial production, basically betting my life on these working when the temps are in the 90’s plus….and they do.
With that being said, yes there are some random crashes, not very wide spread. If you are using it for your lawn at your house and you more or less set it and forget it, worse that will happen (short of the unit actually breaking) will be the need to do a hard reset to get into the app (power switch). Even in those cases, the unit keeps functioning and programs keep running on time. Also there is a program setting you can use to have the unit reset periodically, which will fix the access issue. I use this on only one of my units that seems to every once in a while lose app connection.
Also, for my use case, I access these controllers from anywhere and on an almost daily basis. I adjust and run programs as needed on the spot and have scheduled programs constantly running. I likely have one of the more intensive use cases that these units deal with and I wouldn’t want to change from this system. Yes, I would like to see these issues resolved, but this stuff comes up as hardware and software is changed over iterations.
I can not speak to the qualities of comparable systems, for the record.