Book Recommendations

If you had $20 to spend at Monergism Books (I do), what would you spend it on?

Some possibilities:

• CHURCHES, REVOLUTIONS AND EMPIRES: 1789-1914
• GOD IS RED: THE SECRET STORY OF HOW CHRISTIANITY SURVIVED AND FLOURISHED IN COMMUNIST CHINA 
• A NEW TESTAMENT BIBLICAL THEOLOGY: THE UNFOLDING OF THE OLD TESTAMENT IN THE NEW
• 2000 YEARS OF CHRIST’S POWER: PART ONE: THE AGE OF THE EARLY CHURCH FATHERS
• NEITHER POVERTY NOR RICHES: A BIBLICAL THEOLOGY OF POSSESSIONS (NSBT)
• THE CHRISTIAN FAITH: A SYSTEMATIC THEOLOGY FOR PILGRIMS ON THE WAY
• ???