I don't know what the Nars one looks like but Bobbi Brown makes a smudge brush as well, it looks a bit like the MAC 219 pencil brush but is better, imo. I have this brush from BB and love it.
SEPHORA!!! You can buy the $12 version one... I think the cheap version and the more expensive have the same quality (except one has longer handle =.="). HOWEVER! SEPHORA does have more hair (it's more puffy) than NARS #15...