I have this foundation and was matched with shade 8.0 from the website (it has you identify your shades in MAC, MUFE, etc and gives a number)
the only mac foundation I was is F&B I'm C6, MUFE HD 173 and 18 in F&B, NARS Cadiz and I have drier skin
when I swatched it, seemed too red for me. I have golden/yellow undertones but the first time I wore it, it was great! matched very well and lasted all day long
the second time I tried it...it seemed too light. I had to darken it a bit with my MSF.
there wasn't a huge gap in time between the first and second use so I don't think I'd gotten much of a tan...so I don't know what that was about.
I'm going to continue using it, I actually like it a lot. the coverage is just what I like, pretty light but covers what I need well.