It seems to me that it gives the uninformed a basic overview of what was produced and when and by who and perhaps serves as a beginning point for further research into one's preferences.

For example, I am inclined toward Ithaca NID's more than any other double. What would be the next book I should obtain?

Another question as well. Are there any American Made shotguns that should have made McIntosh's book?

Me? I never miss. This new breed of quail can fly with their hearts shot out!