I had the Companion but sent it home because I never used it. I haven’t seen the Data Book, but there are city maps in the back of Wingfoots that point you to the laundries, etc. The Companion is just “This is why they call it Blood Mountain,” and interesting reading is a luxury, not a necessity.
If you want to save some money, you can always go with an older version of a guidebook. You’ll miss some Trail reroutes and a new shelter or two, but that’s no big deal. Also remember that the Trail is a busy place and if, for example, you get to Erwin and can’t find Miss Janet’s for the life of you, you’ll run into another hiker in no time.
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