At nearly £50, Vander's might seem a bit pricey for a physiology textbook, especially one which is such a flimsy paperback as this (with a distinctly uninspiring front cover). However, it would be wise not to judge this book by its cover.
The book is well organised with a wealth of information. Speaking from the perspective of a medical student, this book covers everthing under the topic of physiology you will need for the course.
The greatest strength of this book is the diagrams, they are always helpful illustrations and a large number of flow diagrams - very useful indeed for understanding complex body systems and feedback loops. I find this most useful, being a very visual learner. The text is also well written.
At my med school there is about a 50/50 split of users of Vander's and Pocock & Richard's Physiology textbook. Having used them both, I found that I did not like the latter due to its lack of diagrams and style of writing. However, some people do seem to prefer it to Vander's, so my advice would be to get both of them out the library and see which one you prefer before you buy one.