Is it better to go big or small?
I have a 6 1/2" wrist(comfortably), and the small fits a 5.5"-6.7" while the large fits 6.3"< .At a pinch i can fit just under 6 1/2", but I am worried if the small might be too small?
I thought I should have gone with the large when I first got it. The small seemed a little too tight when I first bought it. Especially when reading how to use the heart rate monitor, i thought I may have to exchange. I am used to it now. I wear it on the 3rd rung in which is just enough for the band to grasp the end of the strap in place.
Not sure if this helps, but sounds like you are close to the scale like I was.
Personal preference...