Harvard Taiwanese 101
Tainan: King-an Publishing, 2005
Format: Paperback and CDs
Cover price: NT$600
Devised while the author (Yeh) was teaching at Harvard, this textbook is, as the title indicates, an introduction to Taiwanese. The introduction states that the Tai-lo system is used throughout, but on closer inspection it appears to be a mixture of Tai-lo and POJ - it is possible that this was an early form of Tai-lo before the final revisions were made.
In any case, the romanization is not difficult to puzzle out if you are familiar with either POJ or Tai-lo. The English in the book unfortunately suffers from the lack of a native English-speaking proofreader; while it is easily comprehensible most of the time, some of the turns of phrase and grammatical constructions are very awkward.
The book is accompanied by three CDs, and apart from the dreadful incidental music the dialogues are good; very clear and relevant to the text. The lessons are also clearly laid out, and while the planning of vocabulary is a little haphazard, there is certainly much of use throughout the book.