As WTBS books go, I thought it was one of the more even-keeled, though definitely filtered through the lens of JW theology. Not being an expert on world religions, I took most of what it said at face value.
I looked forward to studying it at the BS, but obviously we didn't. Despite it's JW perspective, there are long sections outlining the beliefs and practices of world religions with nary a constesting scripture or WTBS thought in sight (although the slant of the writing lends itself to the whole thing being skewed to WTBS thought.)
In my opinion, a reason it never was studied was because there would be entire book studies spent solely talking about Buddhist or Catholic or Hindu beliefs, and many times not a contrasting JW viewpoint presented. One could come away from these meetings with some genuine interest in these other belief systems and investigate them further, and that could not be allowed to happen!