I love my AC3. Certain things aren't necessary but nice. i.e. ORP if you don't use ozone. Easy to add then with an enaly unit for cheap but w/o you can usually look at the tank and know approx. what the orp is but it's still nice. The pH controlling is awesome too. Now they have an expansion module you can add even more automation to the system and eliminate the need for a lot of other stuff. On mine I run the pH, temp, and orp. But if I got a ca reactor I could either swap out the orp or go with the expansion module. Right now I have a litermeter for the kalk topoff and an extra security statment that if pH rises over 8.5 to stop the litermeter. An extra protection. I still haven't set up the web interface though. The aquanotes program is nice to enter things in that you change i.e. bulbs, water, etc. so that if you forget how long you just look through the log. You can also compare it to the graphs to see if something you did changed something.