I don't know about geography as an A-level but in my experience, I'm finishing year 13 and thank you, no more sociology for me. It is an interesting subject but the way it is structured in the examination it's quite broad. Also it's a content heavy subject so be prepared to have to know a lot of sociologists and what they believe about society. I've been doing sociology for 4 years now, since GCSE and in my experience, I wish I could have change sociology with something else in time.
The subject is lovely and it really helps understand society and you will find a lot of things which you study in the course relevant daily. However, in my opinion and experience, I wouldn't pick it if you're not completely sure that you want to have to learn this much. Also the biggest question is a 30 marker and trust me everyone at least who I know absolutely hates them. I always advise people to chose another subject if they want peace in their life during college XD