Frances Harcourt-Brown is a highly respected vet with many years' experience in general practice, and is well known as an expert on rabbits, having published various influential papers on rabbit disease. As a small animal vet who sees more rabbits than most, I have found this book absolutely invaluable. It comprehensively covers all areas of rabbit medicine, and deals both with well-understood and simple conditions, and with those poorly understood at the time of publication (such as Encephalitozoon cuniculi). The illustrations are clear and helpful.
Although the book is clearly written, it is certainly intended for vets rather than pet owners, and I would think it would provide far more detail than the average pet owner would require. Another consideration is that Mrs Harcourt-Brown is British; for me, that's an advantage, but I don't know how many drugs, etc that she mentions would be readily available in other countries. Also, this is a book of medicine, and as such doesn't cover surgical techniques in any detail.
However, I would highly recommend this book to any vet who seriously wants to consolidate their knowledge of rabbit medicine. All veterinary textbooks are expensive, but in my opinion this one more than justifies its cost. I can't think of a case I've treated where it didn't provide me with at least some helpful information.