I have a few nursing tops. H&M sells them and I love them.
They only have one pattern, i think, lol so I have the same t-shirt with long sleeves (all black and black&grey stripes), short sleeves (black and white) and short sleeves but longer so it's actually a dress.
Oh and two nursing tanks with a built in shelf.
The prices are very reasonable; i paid 25 euro for the 2 short sleeve shirts together. and I think 19euro each for the long sleeve ones. I got some of them in the sales so they were cheaper then, maybe around 15 euro...
They are nice, flattering shirts so I think it's worth it. Organic cotton, too.
And personally I think it makes NIP a lot easier and more discreet if you want to be
(I like being discreet, I would be uncomfortable with showing a lot of skin in public).
I bought the nursing shirts only a few weeks after dd was born, before that I just wore a top that I could pull down enough, and another t-shirt or something that I could pull up.
But the nursing shirts make it easier.