After reading this thread, decided to put my old rock to the test. Went for my daily constitutional yesterday, showered, dusted off the rock and applied liberally under the armpits. Did moderate activity during the day and stayed indoors mostly. Didn’t shower this morning before constitutional. Even if it was 7:30 A.M., in direct sunlight it was hot. Wore short-sleeved shirt (synthetic material…yeah, I know) and walked at a brisk pace for an hour and then climbed 11 flights of stairs to my apartment.
Results : very little sweat and no BO.
Can’t remember why I stopped using it in the first place (purchased it years ago) but I do have to admit it’s quite efficient and – as a few dopers mentioned – really economical on the whole. The only possible caveat would be in the composition of said rock: I threw away the box in which it came and don’t remember the ingredient(s).
But it does do the job.