Supermodel is a really lovely glossy medium grey, great coverage and excellent performance-wise. Just the kind of colour and formula I like. On The Rocks looks quite similar in the bottle but when you look closely and swatch it, it isn't. OTR has a much more brown base and actually has a really fine shimmer running through it. It's not a colour I have much of in my collection and I probably wouldn't have picked it up if I saw it, but I really like it and will definately wear it.
As I'm sure I've said before, I love Leighton Denny polishes so this was a pretty ace present for me. My mam knows me too well - actually, she's even worse for buying beauty products than I am. She uses Creme de la Mer for gods sake!