I bought one a couple months ago, it just collects dust. The readings are all over the place unless it's just plain sugar solution. I've seen talk of "calibrating" the refractometer to match the error between wort and sugar solution, but in my testing, the error has been +/- 1 degree plato~4 degrees SG with different batches of wort. Just not acceptable in my opinion. I've tested my hydrometer with precise sugar solutions and it's dead on. I go with that.