Back when I was nursing my son 4 years ago, I heard about Glamourmom and their fantastic nursing tanks/tops. I wanted to get some but just couldn't justify the cost at the time. But when I was pregnant with my daughter, and I saw them come up on Babysteals.com, I couldn't resist. I purchased 3 of them. (I had tried them on at a local retailer to make sure I was ordering the right size...) When I got them, one had a teeny tiny hole in it, which Babysteals made right, right away, by sending me a similar replacement. So now I have a blue nursing bra top with lace, a nude nursing bra top (with a teeny tiny hole), a purple nursing bra tank, and a light pink nursing bra tank. They are all great, but I wish the tanks also had the wider elastic straps and the nursing bra type closure, rather than spaghetti straps and the smaller flat closure.
The "tops" have slightly wider straps and a secure clicking closure like most nursing bras have. The "tanks" have narrower straps and a closure more like the back of a bikini top. While they do also click securely, it's a bit more fiddly to close them up with one hand (while juggling a baby on your shoulder) and so sometimes I don't get them clicked all the way shut, and then I end up walking around the house with what some might call a wardrobe malfunction. Not cool. HOWEVER - both the "tops" and "tanks" styles have amazing support. They have a secure shelf bra built in, and an extra layer of mesh fabric in the fold down part that really holds things in well. I would never think of going out of the house in a typical shelf bra tank, but I have worn these out (under a hoodie or button up shirt) a ton of times without feeling self conscious at all.
They are very comfortable, although I do suggest getting a size bigger than what you typically wear (I'm a M in most things but had to get the L in the tanks/tops so that the shelf bra elastic would fit comfortably). They are generously long so they cover the post-partum belly area nicely. The "tops" are also made of a material that is stretchy yet holds things together to help give a smooth line when worn under a shirt. They come in many different colours so you are sure to find something you like. Check out the selection and get more information (including where to buy) over at http://www.glamourmom.com/index.asp.