Well the onus is on the hobbyist to put aside their bias hat and just speak to their experiences. Obvious maven is only in the hands of those beta testing it if that is still going on. As you noted - the debate rages on /shrug
OP - you state 'start keeping sps such as acros and want my water to be as stable as possible' which leads me to believe that you are just getting started. Or the display is (frags vs colony). Not knocking experience level but one doesn't really need automated testing. That is a quality of life thing, not a necessity. Sounds like I'm lecturing but not trying to, sorry. Hanna Alkalinity manual test can be done in a couple of minutes. Phosphate, nitrate, Hanna checkers in a couple of minutes as well. Calcium - pick one that is easy to use. In fact all I tested for was Alkalinity but we all have personal preferences.
Point being is the automation is optional. Several to choose from and you will get a lot of varying opinions on them. Mine included. May be easier, and cheaper (not knocking budget), to just get alkalinity, nitrate, phosphate checkers and do a manual test every couple of days and add the data to excel. Within a couple of weeks you will see the daily consumption and trends which is all you need really.