I have mixed feelings on this. Lansley makes a reasonably compelling argument and it contains more detail on both private equity and hedge funds than I've read elsewhere.
However, I wanted to see the overall assertion (that growing wealth inequality is actually damaging to the economy, quite apart from the social and moral arguments) nailed down with academic rigour, and this book doesn't do that.
It's too much of a polemic for my taste, and not enough of an analysis. That said, if we assume that Lansley has been fair in how he uses quotations, then some of the strongest arguments come from the industry, finance, economics and government luminaries that are referenced. When we have these people saying the system is broken, then I think we have to listen.