Madeline requested some swatches of Nars Sheer Glow Siberia with Illamasqua's Rich Liquid RF115 and Cream Foundation CF115. I threw the CF120 in for the heck of it, since she's contemplating a slightly darker shade as well. Hope it's helpful!
I took a small flat brush and blended out - or maybe that's blended in? - the swatches. They're much more difficult to see because three of them match my skin well.
I cut off a smidge of the Nars Siberia in this one, sorry!
I didn't put up Illamasqua's CF110, which is white with pink undertones. You can see swatches of that against CF115 and CF120 here. I've read a lot of reviews about CF110 complaining that this is not a "natural" shade. It disappears right into my skin and looks like I don't have any foundation on, so I beg to differ. If it looks white on your skin, than it's not your shade, plain and simple. Oh look, a chicken! Sorry, got sidetracked for a second.
My skin is quite pink, and although I do try to minimize redness from rosacea, but there's that line between minimizing and wearing the wrong shade. On me, Nars Siberia is quite a bit more yellow toned than Illamasqua's 115. I can wear it on pinker/redder days and it doesn't look bad at all. It's the best non-Illamasqua traditional foundation I've used since switching back from minerals last September.
The 115 works very well. It's really a good match, and if I didn't have the 110 to compare it to I'd be completely in love with it. I wear this more and more often in the warm weather, when everyone around me is tan. It give me a hint of color but doesn't look fake, wrong, or completely off on me.
The 120 is not only a shade darker than the others, but also considerably more peachy on me. I wore this twice to work, thinking it was passable, but it's really not. :( It's sort of a shame because it did a great job covering up my rosacea. I tried to apply it lightly to my cheeks and then use 115 everywhere else, but after about half an hour it's just too noticeable on me.
If you have a Sephora or other store near you that carries these products, it's best to go in and swatch them on your own skin. Don't buy it then and there - leave the store, walk around for about 15 minutes or so, and check the swatch in natural light, preferably when it's nice and sunny. The store's lighting may not be the best, and the makeup might need a little time to absorb/oxidize and settle in. Make your decision after you've done these things.
I hope these swatches are helpful!