I'm between a 12 and a 14, never ordered from Great Plains and wanted to know how their sizes come up. They have their medium as a 12 and large as 14. In gap and m&s id be medium, but large in uniqlo and prob large in zara. Im looking at buying some tops in the sale online. Im quite busty so should I steer to large, or are they quite generously cut? Any advice greatly appreciated.