I love the performance and versatility of a good flat-top brush. Kevyn Aucoin Super Soft Buff Powder Brush is one such makeup tool: wide, very dense and soft. I use it either for liquid foundations just as I do with Stila No. 21 or for powder, especially when I'm going for more coverage.
I don't know why such brushes are often sold and labeled for blush application- they are buff brushes, and unless you actually mean to buff a huge amount of pigment onto your cheeks (really not a recommended look), you'd be better off either with a much smaller flat top brush (Julie Hewett Cheekie or Hakuhodo Mizubake) for cream blushes or a domed/pointed blush brush. Kevyn Aucoin's Super Soft Buff Powder Brush does enough for me without being dipped into blush pans.
The nicely weighted handle is similar to all Kevyn Aucoin brushes, comfortable and pretty. The head size is right between my other two flat tops- the Stila one and Hakuhodo G527M. The latter is obviously not as flat as the other two and is only used for powder, while the Stila and Kevyn Aucoin are amazing with liquid foundation and tinted moisturizer; don't be afraid of using natural goat hair brushes for such purpose. The Kevyn Aucoin brush is not as soft as the Hakuhodo but definitely soft enough. Its weakness is in density- it could have used a little more hair. On the other hand, Stila No. 21 might be denser but the two newer ones I bought shed quite a bit (I don't think my old one ever did).
Bottom Line: a very stylish workhorse.
Kevyn Aucoin Super Soft Buff Powder Brush ($46) is available from Barneys, Bergdorf Goodman and Dermstore.com.
All photos are mine.