The set I bought because of the good reviews here on Amazon and since it is from Nintendo itself.
The guide describes short and simple and the handling is very easy. After the cleaning process was "Super Mario Galaxy", which was not recognized previously, easily recognized again.
For the price of 5.99, it is worthwhile in any case, before you send your console to clean Nintendo to try using the CD itself be drive to move it to the correct reading.
I helped it and I'm very happy with it, so I can recommend it to anyone who has read errors at his console.