Amazing pictures, ease of use with color codes on the pages, small format, solidly bind together, extensive coverage... it is truly a great field guide. It is not, on the other side, a perfect book for definitive mushroom identification. In order to keep it pocket size, and keep pictures at a reasonable size, the text identifying mushrooms is quite concise and some details are often missing (e.g. a 'similar mushroom' section indicating the specific difference to look for). As far as I know, it is the best pocket size field guide available on the market right now but the dedicated mycologist or the amateur mycophage still need a more detailed book at home... and these encyclopaedia can hardly be brought on the trail.