I really like these bralettes. I bought 2 racerback and 1 of the traditional clasping ones. They are all very comfortable and supportive. The reinforced lines under the breasts really give a nice, natural shape, which I love.
I do, generally, prefer a more seamless bralette, which these are not, but they feel sturdy and like they will last a long time.
The one star I took off was because I do find they dig in a bit along my back, which is why I like seamless. It's not uncomfortable, just a personal preference for not having the visible line of the bra.