Pluses
+ bird illustrations are high quality National Geographic illustrations
+ song recordings included & easily accessible
+ less costly than competition
Minuses
-plates are *much* too small (about 1/4-1/2 the size of the same plates in the field guide) to see real detail
-search frustrating (four different search types, if you search for "Goldfinch" hits only appear in one)
-lists similar species, but does not provide links to them to do immediate comparisons
Gavia about National Geographic Birds: Field Guide to North America