Yes Ryan Cragun is very good. Here is another he wrote:
Lawson also wrote an article decades ago demonstrating the differing trajectories of JWs and SDAs: SDAs have become a denomination of Christianity while JWs remain sectarian in character.
Their work is a good counter to Rodney Stark who at one time argued both JWs and Mormons were on course become major world religions in this century.
I know all these artilces are not accessible, sorry.