Smashed is certainly pretty; it reminded me quite a lot of a polish I like so much I've put in in my Top 20 the last two years, Estée Lauder Ultra Violet. Here are the bottles, Smashed on the left, Ultra Violet on the right:
And here they are on the nail, two coats with topcoat in both cases; left to right—Smashed, Ultra Violet, Smashed, Ultra Violet:
The difference is quite subtle. Let's zoom in to see better—Ultra Violet on the left, Smashed on the right:
Out of the lightbox; Ultra Violet on top, Smashed on the bottom:
Ultra Violet's shimmer is more silvery and less colorful than Smashed's, lacking the pops of blue violet. The base colors of the two are really, really close. If you've already got Ultra Violet, I'd say you can skip Smashed. They're not dupes, but the overall effect is so similar that I bet I could wear these on alternating nails and no one would notice I had two different polishes on.