First off, I should make clear that I have respect for Thomas Taylor, the translator of this work, as a translator. He was certainly competent in that role and I have no real complaints about that aspect of his work. During the Romantic era, he made not only Plato's writings, but many other Platonist and Neo-Platonist writings available in English translations--many for the first time. I, personally, have a number of his translations. Now, that being said, his own philosophical merits are not very significant. He was really less of a philosopher and more of an occultic theosophist (in the Blavatskian sense) before there was such a thing. His own writings, including his introductions, books and translation notes, have a tendency towards neo-pagan sycophancy. This tendency can be taxing on the patience of the reader more often than not. Spending some time reading his commentary on Maximus of Tyre, I can appreciate some of his ideas within the context of Romantic era Idealism.
I read this collection of Pythagorean and Neo-Platonist writings simply for the sake of completeness. I am trying to read as much of the Platonist school of writings as I can. These writings certainly qualify, but, unfortunately, there is little of philosophical value and much that is worthless pagan propaganda. Obviously, Thomas Taylor, himself being a neo-pagan, was trying his hand at proselytizing. This was of course the golden age of Freemasonry and other pseudo-philosophical and pro pagan secret societies.
There are a few things here and there that are interesting in this collection, but not much. The only thing that is really worth recommending is the Sentences of Demophilus. I've just read the Pythagorean Sourcebook and Library and this work was for some reason omitted. I personally skipped the pagan hymns of the translator because his notes are often sycophantic enough, without also imbibing his lauds of various deities.