Yes SDAs and Mormons make interesting comparison with JWs. Check out this article that compares growth in these religions.
From my own recollection SDAs are particularly strong in certain African countries, including countries such as Kenya where there are few JWs. The SDA emphasis and support for education is apparently a major attraction for Africans and people in South America. A big contrast with the compete failure of JWs to offer such benefits to their members.