The two photos above are indoors, in the the indirect light of my lightbox. I was rather unexcited by the effect, a very dark plum with the shimmer pretty much disappearing into it. When I went outside into the sun (picture below), I could see the pink and purple and bright plum of the shimmer, and that was pretty.
Being a purple lover, I was sure I'd find at least one dupe of this in my collection. Based on the shimmer and color in the bottle, I picked a couple from my purple drawer to compare.
When I put the Borghese and Sally Hansen on my nails (both were two coats, like the L'Oreal), I saw they were more blue-toned and obviously shimmery.
In the sun, even the shimmer on Plummaggio Purple and Spark showed more blue than the Luminsecence.
I'm still convinced I have something close to Luminescence; I just need to find it. Maybe that's why L'Oreal only put one of each in the display; they knew the colors weren't that special.
Of the this group, my favorite is Spark. Unfortunately, that's been discontinued along with the rest of the Lacquer Shine line. Diamond Strength is still going strong but my beloved Lacquer Shine, not so much.