Vacuum deposition treatment on gemstones?

[SouthernGent]

What's the consensus on vacuum deposition treatment of gemstones - good, bad, useless, indifferent?
I came across some Swarovski "paraiba" topaz in which vacuum deposition is used to apply a film yo the pavilion of the stone in order to give it it's color.
Any opinions?
Here's a video showing it:

 

[Bron357]

Swarovski is a brand, Austrian, they make lead glass which is used in costume jewelry, it’s not a gemstone.
Vacuum deposition is just a fancy way of saying it’s got a microscopic coating of color over the glass.
It would wear ok in earrings or a necklace but in a ring or bracelet I think it would “abraid off” over time.