The Wee Frees were a splinter of a splintering from the Church of Scotland. All were and remain Presbyterian so nothing really to do with doctrine etc. More about the running of the church at a local level and the appointment of ministers etc. Though the Free Church has tended to be more strict and less modern in their thinking than the mainstream Church of Scotland. Hence the historical no sailings on a Sunday etc etc etc. There are very few, if any, congregations here in the south of Scotland. Some in the bigger towns and cities but mostly in the Highlands and especially the Hebrides.