Tele.ga has more features (RSS, sitemaps, etc.) that I still plan to implement for Telepost. The disadvantage of it that is built on top of the Bot API that has limited abilities. For instance, Tele.ga can't fetch history of your channel (works only for new posts) or handle message deletion request. Telepost has close integration with Telegram; your blog will be complete and always be up to date. Also, Telepost also doesn't require adding a 3rd-party bot to admins of the channel.