I went with my SA's suggestion. She said if I am a 16 in bracelet I would be a 17 in cuff ~ they are nearly the same size with the cuff being a touch larger. They stack perfectly together and unless you really inspect them on the wrist they look like the exact same size.
I generally wear the cuff closest to the hand and it will move on it's own, away from the other 2 (if that makes sense). If I wear the cuff in the middle of the bracelets they all basically stick together.
I'm not sure if this varies by wrist but for me the size 16 cuff was snug and really hard to put on/take off.