Good plan. See my previous comment; I did my MSc on classifying fake reviews. The behavioral / non-text features are far more useful than the text, based on all

Good plan. See my previous comment; I did my MSc on classifying fake reviews. The behavioral / non-text features are far more useful than the text, based on all the research. There is no technical reason Amazon could not capture all the signals, except for the scale of the effort. So I'd say someone has decided it is not worth the effort/cost given the likelihood it won't improve sales that much. As for NNs, .... an ensemble of classifiers would be best (but of course I'd say that).