Women's cozy racerback seamless pullover wirefree bra, style g39f

I bought this wireless sports bra for a surgical procedure I had and it was perfect! I could wear it into the operating suite under my gown since there was no metal and it was comfortable to wear home after surgery too. Great fit and true to size. I got a medium :)

I love these. So comfortable. BUT the sizes are inconsistent between colors. I have an old redish one that's a M and fits great. Tried to replace it with a light blue one, also M, but it's a bit tight. So I ordered 3 more, 2 mediums, hoping the small one was a fluke, and one large. One of the mediums is great (dk blue), one is way too tight (pink), and the large(black) is comfy for sleep but too big and unsupportive to wear out. There also seems to be a huge sizing change from M to L. The large I could almost wear as a crop top - it's much longer in the straps and the band is much wider and curls up.