Trailer Life is the one that we have come to use. Woodall's is owned by the same parent organization, although they do have a seperate staff. There is also Wheeler's guide which is a completely different organization. The other two are owned by Affinity Ent. who also own Good Sam, Camping World and a bunch of other magazines and such. Wheeler's is an independant organization and they do offer some listings not found in the other two. But we have found that the best directions are in Trailer Life, and if you are a Good Sam member, only they list what parks will give the Good Sam discount. For that reason we now only buy the one from TL.