I just picked up a 180 brush not too long ago and I really like it
. I knew when I bought it that some people don't like it, but I don't have very prominent cheekbones, so it's pretty important for me to blend my cheek make-up together really well. I just jam on my contour, blush and highlighter until they're a bit darker than I want them to be in the end, then I just take the 180 and make little circles where the different powders meet. I wear Studio Fix Powder foundation only (my skin is pretty good on its own, I don't need crazy coverage), and it does lift off the foundation if I blend it too much. So I don't actually know how well it blends powder into liquid foundation because I don't wear liquid or cremes, but it works quite nicely when you're blending it into powder. You should only pick one of these up if you're having trouble getting your contouring and blush to look natural, or if you're lacking in the cheekbone department like I am. Otherwise, just try the 188, which has many other functions (applying contour, blush, highlighter, touching up foundation) besides just belnding powder (which it certainly can be used for...the bristles aren't as stiff as the 180's, but it still works).
And if nothing else, it feels nice on your face when you use it. Bad reason to buy such an expensive brush, but it's true