I had always used "Lexbrongs" (if thats how you sell it) before they made the upgrade for Logos. Logos has been with me door to door and in Sabbath school meetings. Its much better than using a back pack full of books..It has truly been a blessing just wish more people knew or used it. I post things from Logos on facebook all the time seeing how most on them are 7th day Adventist only to hear crickets.