I am 52 34D and bought a size small. This top was awesome in Hawaii surfing for 7 days.
The fit is perfect and sat over my curves well without riding up.
I also wanted maximum protection from the sun so the mock turtleneck was ideal for neck protection.
Also for me the arms were a bit long which is what I wanted because I like to cut a slice in the seam to pop my thumbs through to bring the edge over my wrist and the back of my hands. This helps with skin protection and for the garment to stay secure against my skin while surfing and swimming.
The fabric hand washes nicely and drys quickly in the shade.
I paired this item with the HIGH WAISTED 2mm neoprene swim pants I purchased from Amazon. I am 52 135# and the xs in the neoprene pants were perfect. You definitely want a high waist in neoprene pants otherwise when neoprene gets wet your bottoms will slide down and slip off. (Dont ask me how I know this first hand. Lets just say those around me had a TMI moment!) The top and bottoms are fitted when dry but really stretch when wet and the two items made for excellent sun protection and warmth while spending 2/3 hours in the ocean. For face protection I highly recommend VERTRA face sticks.