I use one and its great. It does take setting up the code but as a previous post said, the RA forum is very active and I've gotten choding help with 24 hours almost any time I post a question.
I am not a programmer, but was able to use help files, the forum, and reverse engineering choice stuff off the forum to make my set up without much issue at all. Basically just copied, pasted, changed names and values to suit.
As with any aquarium system, every set up is different so it does take some customization.
I run the RA Plus on my 90 mixed reef with the pmw dimming expansion, 1 power unit, the head unit, and a dosing pump for carbon dosing vinegar. I haven't had any issues with it yet.
I'm completely happy to get such a powerful reef controller for the price point. He's saved me lots of money over other systems. . . But I did put in the development work to right the code for my lighting and everything.
I also plan to add another doser for Mg and possibly another power unit and battery backup for my dt pumps to it eventually. Then it will be time for a new system. Lol
Feel free to hit me up if you have more questions.