I am a 34DD, and the small (supposedly 32-36) is too small in the band for me.  I am going to keep it as I know the elastic inside will stretch with time and it will be come more comfortable.  However, the bra inside is kind of strange - there is a hook and eye closure that would help if you had a very small torso (ie, 32) but otherwise is merely constricting for anyone with a 34 or 36" band. For some reason, the fabric over the band also nips in right at the band, giving it a slightly weird appearance on the outside. Also, it appears higher at the neckline in the photo than I find it to be when worn.  I think it's better than the Bravado nursing tank (which I also own), that is very low cut and offers only the same support you'd get in a basic shelf bra - at least this is a step up from that.  But, if you are looking for a more modest neckline, this isn't it, and if you're 34 or higher, I suspect you can't go up a size to the M without the band becoming too large.  It's just too hard to fit such a large range of sizes comfortably.