Last Friday Night is from the OPI Katy Perry Collection released in 2011. I've never wore it on its own before, but I've heard that the polish color in the bottle isn't the same as when you apply it onto the nail. Regardless of this, I still really like this polish because I love glitters! Last Friday Night has fine particles of glitter in it as well as hexagonal glitters, and the base is a sheer blue color. This polish has a lot of dimension since there are different types of glitter in it.
As for Ballet Slippers, I think that it's a really pretty nude polish. I don't usually wear nudes that often, but I've had this polish for awhile and have never tried it so I thought I'd give it a try. Like most Essie polishes that I've tried, the formula can be a little streaky if only one layer is applied. I think you can get away with two layers, but I did three just in case.
With the two polishes combined, the color on the nails ends up looking like a very muted periwinkle. I think this would be perfect if you're wanting to wear something that is less dramatic but still has glitter on it. If you're not used to wearing glitters but would like to ease your way into using them, then you might want to try this combination since it's a little more toned down.
All in all, I really like these two polishes together! :)