I like these brushes more than the ones you get in a big pack, they seem to hold up better and are easy to see if paint remains because of the color of the sponge. I have used this with stamp pads too, very versatile.
They are just okay. I can't say that they are awesome or anything extra special though. I bought a pack of them thinking they would hold up better than the cheap ones I buy at Pat Catan's ($0.20 each - and you can buy 1 or 2 if you want you don't have to buy 5 or 10)
They held up about the same as the ones from the Pat Catan's.
I will mention this though... if you are using any foam brush for the same project and have to stop in the middle... put them in a freezer bag (don't worry about rinsing if you are going to repaint in the same color paint) freeze them until you need them again and thaw them out.