I have worked through much of the Plato book and have generally found it useful. Essentially what they do is take a passage, simplify its syntax (ie changing participles to finite verbs, changes to the word order..etc) for the first reading and then slowly add those elements back into the passage over the course of three or so readings.
As for vocabulary, all they really do is give a list of words neded for the present passage. In addition they also feature some grammatical explanations that are particularly relevent to the present passage.
Overall, I was happy with the book, although I do still find Plato rather difficult. I have not used the Homer book.
Anything else you would like to know about it, let me know...