I think his book, "I Will Teach You to be Rich," is good for setting up a financial framework. You don't have to take his advice on purchases, and instead go the Mustachian way there. But for setting up the financial framework that you can fund with your dollars, I think the book is great for that.
As far as his other material, such as the book on negotiating lower rent, I have no idea of its quality. But it would, of course, be handy to lower expenses wherever you can. So it's worth learning about, if the information is reliable.