I am thinking of investing in a leather biker. I like the Oasis ones but wondering what size. I want it to fit neat but am ample of bosom and don't want to get all flattened out . But then again, if I am more likely to wear it open, I don't want a looser one flapping about. What's your experience of the sizing? I'm a size m or 14 in most oasis tops. I already own a faux leather from oasis but still feel weird about it. I always said i would never get a fake leather jacket but materials are def getting better and I gave one a try. Thats a size m from oasis and its pretty tight on the chest but hoping to lose weight. I still always wonder if people look at it and say, yep...fake!
I've got the stevie jacket from oasis and it's quite fitted when done up. I'm a small 10 or and 8 but I'm 30f so had the same concerns as you, I got a size small and it's perfect. I don't generally do it up and even if I do, not all the way but I could if I wanted to iyswim.
I'm a 10/12, usually a 10 on top, and my Oasis leather jacket (biker style) is M. I often wear it done up, because I live in Scotland! I'd generally buy S in tops or dresses in there, 12 in jeans or skirts, if that helps any.