proplog2, I too wondered why JWs have never studied that book...a Bahai friend was impressed by the information on the Bahais and felt it was fair and accurate.
Here are some larger articles and publications on Islam and the Quran over the years. The "Mankind's Search for God" and the brochure should still be available through KH literature sources or probably on Ebay or other used book sites.
11/99 Kingdom Ministry page 8
What Will You Say to a Muslim?
Brochure 1999 The Guidance of God—Our Way to Paradise
Mankind’s Search for God (1991) pages 284-302
Chapter 12 Islam-The Way to God by Submission
7/22/89 Awake pages 21-4
Part 14: 622 C.E. onward-Submitting to God's Will
Religion’s Future in View of Its Past
w53 11/1 653 Examining Islamic Teachings ***
w52 4/1 209 The Quran-A Literary Miracle? ***
w52 4/15 233 The Quran-Confirmatory of Previous Scripture? ***
w52 5/1 277 The Quran-Harmonious with Itself? ***
w52 5/15 297 The Quran-of God or of Man? ***