I'm normally an XL in tops and ended up going with the 3X in this one as I'd read a lot of reviews saying they fit extremely small.  I was glad I did, because this 3X basically fits like an XL or *maybe* a small 1X.  I'd recommend sizing up considerably if you're busty and don't want something skin tight.

Other than the side, it feels very comfortable and well made, and I will be ordering more colours when I need them.  I really like the sleeve length on these and the neckline is very flattering.