I love this collection. The colours are great, as is the formula (2 coats shown). Surprisingly, I did not have close dupes for most of these, so the comparisons might not be too useful to you, but I thought I should show them anyways to help you get an idea of the colours.
Essie School of Hard Rocks - I was dying for this colour. I think it's awesome. For someone who has a lot of teals, I was really surprised to find I didn't have anything as greyed out as this shade...
Comparison: Essie School of Hard Rocks and Misa Dirty Sexy Money - I decided to compare it to one of my fav dusty teals. Totally different.
Comparison: Essie School of Hard Rocks, Orly Sapphire Silk, and CND Urban Oasis - This was requested by a reader. I don't have OPI STWD anymore XD
Essie Bangle Jangle - Nice greyed out purple.
Comparison: Essie Bangle Jangle and OPI Done Out In Deco - I had been wondering what this polish would look like against one of my favourite light purples, DOID. Turns out, the OPI is a tad warmer. I'm not sure which one I like better, though.
Comparison: Essie Bangle Jangle and Essie St Lucia Lilac - Compared with another favourite light purple of mine, Essie SLL is really different from Bangle Jangle. I feel fine keeping both :D
Essie Cocktail Bling - Yummm. Greyed out periwinkle, almost?
Comparison: Essie Cocktail Bling and Zoya Caitlin - The closest shade I have to Cocktail Bling was Zoya Caitlin from earlier this year. As you can see, though, the Zoya is much much darker (although very awesome in its own right). Love both.
Essie Size Matters - I'm always on the hunt for a good red to go with my skintone, and I think this one is great. Very blue-toned red, it almost seems raspberry on me.
Comparison: Essie Size Matters and Essie Limited Addiction - I find photographing reds to be a challenge. Actually, these are not as close as they appear. Limited Addiciton is quite a bit warmer and Size Matters is definitely blue compared to it. Both have a lovely formula though!
Essie Bobbing for Baubles - Beautiful dark blue polish. I thought it might be close to American Apparel Passport Blue, but I gave that away a while ago, so I couldn't do a comparison.
Comparison: Essie Bobbing for Baubles and Misa Office Polish-tics - the closest thing I still own was this Misa (which I adore). The Essie is really dark, but doesn't look black.
Essie Brooch the Subject - The only one I was waffling on was this nude. I don't think I like it that much on my skin tone, to be honest.
Comparison: Essie Brooch the Subject and Essie Jazz - I compared it to one of my favourite nudes, Essie Jazz. BtS is quite a bit yellower than Jazz.
Comparison: Essie Brooch the Subject and Orly Country Club Khaki - Compared to my other favourite nude, Orly CCK, BtS is also quite yellow compared to the Orly!
So, there you have it. I highly recommend this collection. It might be boring if you're not a creme-lover, but if you are... woo baby! If you guys have any suggestions for additional comparisons, let me know! I'll try to do the comparisons if I own the polishes :)
I hope this was helpful!