RCM Harmony Exam preparation?

Question

I passed the harmony 3 exam and will pretty soon prepare for the harmony 4 exam. I used Grace Vandendool's "The Basics of harmony" book to prepare for the harmony 3 exam. But many people say that the Harmony series by Mark Sarnecki is better. Which series of books should I use? Grace Vandendool's, or Mark Sarnecki's?

Answer 1

I used Mark Sarnecki's workbooks for Rudiments (preliminary, 1, 2).

I'm taking harmony right now and I use a workbook called "Materials of Western Music", by Andrews and Sclater; it's green. Harmony 4 should be red.

I have friends who have taken harmony and I have never heard of those books before...