I did an OU degree and am just about to start a Master's with them as well. I think distance learning is a particularly good option if you want to study alongside other commitments (e.g. work, caring, family etc) or if there are obstacles which might prevent you from studying face-to-face (e.g. financial issues, disability etc). You do have the support of a tutor for each module, so academically speaking there's someone you can ask questions of and get help from. However, you get less of the social side of things since you're studying alone and only connecting with your fellow students online or via the occasional face-to-face tutorial.
What is it about distance learning that feels like a particularly good for for you?