Thanks - I'll be pretty static so not too worried about travelling. It's the leaving the country vs border run that's making want the 6 month at the moment.
6 month visa is £125. 3 month is £25. I'm wondering what the benefit is of getting a 6 month one over the 3 and then applying for another 3? Is it because the second 3 month visa isn't guaranted? Thanks for answering all my questions.