So anyway, I have two concealer brushes, Bloom's and Bobbi Brown's.
Bloom concealer brushes are made from taklon, a form of synthetic fiber which is perfect especially if you're using cream concealers. Generally, the best concealer brushes are made from synthetic fiber. I like Bloom's concealer brush because it's soft and it's wide, which helps in spreading the concealer more evenly.
The Bobbi Brown concealer brush has a narrower, more tapered tip, which is fantastic for hard-to-reach-areas. I found though, that it hurt the area under my eyes when I tried to apply it. It's good for depositing just the right amount of concealer, but then I'd have to put the brush aside and use my fingers to spread it around. I use this on problem areas like maybe a pimple or the sides of my nose. I also like that this brush comes with a cap so you can bring it along in your kikay kit and not have it smudge everything in it.
All in all I use my Bloom concealer brush more, because it already does everything. It packs in just the right concealer and I don't have to use my fingers or sponges to spread it evenly. Still, these are two excellent brushes and I would definitely recommend them if you're looking for concealer brushes.