I can't say much for chad's, I never used them
But I liked examkrackers orgo, I thought it was short and to the point. Their last chapter on NMR was AMAZING, a 100 times better the kaplan book books.
But honestly with orgo, the best thing you can do is get kaplan blue book and your old college orgo text book, whenever you come accross a topic your weak at, crack open the text book