Lionel Train catalog/guide book differences?

I was wondering… what is the difference between the Standard Catalog of Lionel Trains 1945-1969 written in 2004 and the one in 2006 BOTH by David Doyle? IS it just “values” for trains? Or were there more (Critical) additions to it? I don’t really care about “values” or the collector aspect of Lionel trains, so would the older book be just as good as the newer one? (other than values [;)] )

Also, am I to understand that the Greenberg’s Repair and Operating Manual for Lionel Trains, 1945-1969 is a different book?

Is one better than the other? OR are they the same? Is one more of a guide to “collecting”? What do you guys recommend? Do you recommend getting BOTH?

Thanks!

Jim

Read this:

http://www.trains.com/TRC/CS/forums/323210/ShowPost.aspx