books (purple one) are expensive and are not as useful as the Manhattan GMAT
prep books (red one). They are two different companies, though with somewhat similar name. I did bought the Manhattan Review
for verbal, but only did couple of pages and it is now sitting on my desk. I don't even know why I bought that at first place. Anyway, Manhattan GMAT
prep does have great books. I have all 8 of them. I highly recommended.