Duochrome anything is a hit with me and when Miss Sporty recently released 3 new Metal Flip nail polishes that hit the spot.
I picked up Beetle Wings (unfortunately the name isn't on the bottle) which flips from golden bright green to a pretty rosy copper. The duochrome is strong and for £1.99, it's a decent buy.
Here are some more photos:
However, as pretty as the polish is, it isn't without it's problems. The wear time is terrible, lasting only 1 day for me before chipping quite noticably. Also, the bottle is very small at only 7ml - but for £1.99 that's not too much of a disappointment.
I'm glad I bought it but I'm not particularly interested in the other 2 options so a wider shade range being introduced would be fab.