When comparing the colours in the pans, they don't look similar, at least not for me. Hipness is more of a coral pink shade in the pan while Deep Throat is more peachy pink. However, when you swatch them both next to each other, you can't really tell the difference.
I swatched MAC Peachykeen next to Hipness because I always think it looks quite similar to Deep Throat but it's a slightly darker shade compares to Deep Throat. I'm a NC35, by the way. My photos were taken under natural light.
If you already have Nars Deep Throat, would you go for Hipness?