Lets face it, field guides are of limited use. Either they are full of pictures of robins, or are about 500 pages thick and need a truck to cary them around in.
I know that it is heresy to suggest a birder should carry a guide around with him, but that is precisely what this book is ideal for. It only covers the confusion species, has some of the best pictures of any guide, and fits neatly into the pocket of almost any coat.
This isn't an alternative to a field guide (get the Collins bird Guide too!)but for those difficult to identify swines of birds this book is a brilliant addition to your arsenal. I can't recommend it highly enough