MSF Natural-boring skin toned ones. LOL I use these to set my liquid foundation. Just a few swipes on it with a powder brush, over my face after I've applied foundation, then I put on blush etc.
MSFs-the coloured/possibly glittery ones. These I use primarily either as a blush or over my blush. Or just wherever I want some highlighting on my face/body. I know the MA who was explaining them to me last year told me about how you could swipe it on your décolletage to be all shimmery when you go out.
I don't think these (correct me if I'm wrong) would be good as a bronzer. A lot of times with the highlighting factor and possibly glitter if you try using it as a bronzer you may look either greasy or like a disco ball. Or both.