I've had my RK2 for three years with no problems. It is controlling all my lights,heater,return pump, skimmer,calcium reactor,cooling fan for lights,and a pair of Tunze nanostreams on the wavemaker, plus the feed pump for my reactor. Oh and the light for my refugium. The thing i like about it is anyone that can set a digital clock can figure out how to run it. There are no "if statements" to deal with, you just pick from the menus and configure as needed. So when i was 1200 miles away sitting in a boat on a 300 acre lake fishing i was able to answer my cell phone and explain in very quick simple terms how to deal with shutting down the right things to clean the skimmer to my mother who was kind enough to watch over my animals. I'm sure there are some units that have problems but i think you will find that with any of the controllers or any electronic device. Every controller company has a forum on here and they are full of people who are having one problem or another be it a quality issue or self-induced stupidity.