Steve Deneff remains IMHO, the leading author on holiness in the modern era. He is basically the lone (Sorry Drury) resounding voice of The Wesleyan Church and Wesleyan Arminian Theology.
This remains my favorite of All of Deneffs works thus far (I have not read soul shift yet?) and is informative and challanging.
If you are a believer who desires a deeper walk (rather than just saying it out loud), and desperately want to have your ideals and actions challanged this is a book to read!