Adding the uv product to your injection or colored plastic product puts it inside the bait. On transparent colors that means its influence under the sun is going to be more noticeable. If a leg breaks off a frog, the stump will still have the glow at the break. I use the uv in many of my transparent colors, white pearls and clears. I don't use many solid and opaque colors so I don't add any to those when I do make them.
Most of the shiny top-coats are applied as an eye sealer. Its just a clear plastic. I add the uv to all of my top coats and it is there that uv does its best on solid and opaque colors. The top coat can be added to any bait to boot up the sheen on the surface or to help assure sealing at welds from laminating, not just seal eyes. I don't see an appreciable increase in sheen or shine from using uv in top coats however uv in top coats that go over blues and purples does seem to make those colors bounce nice. Blues and purples are closest to the uv light we cannot see and I think the visual limits of the uv we can see is close to the invisible limits we cannot see so some cross-over between those two elements is there to bring those blues and purples to liven up more. Top coating also helps to pull color out of the plastic under it. I'm not talking about bleeding I am referring to the top coat amplifying the colors found under it and making them shine like no tomorrow. Top coating will add to the bulk of any bait that gets it and when I top-coat I always avoid the tails. Top coating an entire bait is tricky and may require rather large vessels to hold the clear plastic.
I believe in uv additives and use them. I do believe they do better where light hits them and surface application just makes sense in that regard.
