I want the gel top coat without actually having to use gel polish. We all want the look without replacing our collection of polishes. Some of us don't like the chemicals.
The Good- The essence is a winner because it is shiny and the "plumping effect" makes your nails look like a cushioned glass effect. The great thing is it's only $3.
The bad- You can only use half of it and it is difficult to get product out. Be prepared to go through many of the essence because the product goes fast due to the bottle design.
I love this because I got complimented on my gel manicures. They absolutely had no idea.
As for OPI I don't even reach for it.