I'm not sure what someone would gain from cheating anyway? Some fictional points which don't mean anything? Can't a person devote their time to actually wanting to learn a language more so than the average person without being branded a cheater?. That being said I have used Memrise a lot and I'm not sure on it yet, I much prefer Duolingo and Babbel at the moment, Memrise is more at the back of my list.