Ooh, a brush thread!
I have the 191 as well. While I love how it feels on the skin, I'm not sure what to use it for, since I don't really use foundation. I do like it better than the 190.
I just purchased a BU of the 287, because I love it for concealer. I bought it on eBay, since the german brush prices are crazy. I know it can be scary purchasing MAC brushes from eBay, but so far I've only had good experiences.