When I was swatching Illamasqua Radium (R) I was thinking if I have anything close and didn´t think of anything, so I took it off and went to edit the pictures. And then I remembered! OPI Who The Shrek Are You (WTSAY)!
I was so curious to see these side by side that I made the comparison today :) I was wearing Shrek a few times and I really like the shade but now that I see these two together I would have to go for the Illamasqua. There are a few differences. First is the color, I think that is obvious from the pictures. Second is the shimmer that Illamasqua has and for me that is a big plus :) Third and also very important is the formula and coverage. Illamasqua is easier to apply, although I didn´t have any problems with the OPI either. On the pictures both have two coats and I think OPI would be better with three, there still is some VNL.