Me too! That's the downside of drug store foundation
I bought it on a whim at Ulta a few weeks ago, and I really like it! I had intended on returning it if it didn't work out, but I'm glad it did.
I have neutral undertones (I have a mix of blue and green veins), but I pull a smidgen more warm than cool as I have a little bit more yellow in my skin's cast. I was matched to NC15, but it is too yellow for my skin. I use a MAC 187 to stipple and buff the Revlon liquid foundation in my skin. I like the Vanilla shade because it doesn't have strong yellow or pink in it, so it works for me. I'm not sure how it would work on strongly warm or strongly cool undertones. I think Gracie90's comment on Matchmaster foundation would be a good route to go