I just picked up 2 of the Nails Inc Mirror Metallic polishes at Sephora last night. This is Cheyne Walk, it's a purple/gold/olive multi chrome with a pearly metallic finish. I'm wearing three coats and no top coat in the pictures. I found the formula to be very easy to work with, thin but not runny and opacity was easy to achieve. I think it looks good with out topcoat, but if you wanted it even shinier I imagine that one coat of SV would do the trick.
There are LOTS of pictures today because I just could not photograph the multi chrome effect accurately. As you can see it varies between brilliant purple to shimmery olive depending on the angle and light. This polish is very pretty and I'm glad I brought it home