Just a quick share:
The owner of the salon where I booth rent (Patti) has been a CND Shellac ("Wildfire", to be exact) lover since its release in May, 2010. Her favorite color since she was a child has been cherry red... the color of old Mustangs, and her long-held vision of "glamour". It also helps that this guy she's been seeing LOVES that color on her nails, and owns at least one fancy car in that color.
So, when I brought OPI GelColor into the salon, she balked. It took quite a bit of convincing; I even promised her I would remove the GelColor and apply Shellac if, within a week, she didn't like the GelColor. We chose Big Apple Red, because it's the closest GelColor to Shellac's Wildfire... and still, she was unsure about it when she left my chair that day.
A week later, I asked her thoughts. "It's not rubbery like Shellac..." At the time, I had no idea if that was good or bad; it's true, though. Shellac, being a hybrid, is rubbery. It's meant to bend a little with your natural nail. It won't do that on an enhancement, of course, but she doesn't have enhancements. This bendiness is also one of the reasons why Shellac doesn't do so well on nails that are prone to peeling &/or are super-thin... too much bend will break the Shellac, and it'll come off.
Another week went by and, due some some snow in our area, she had to reschedule her appointment to accomodate some of her clients. By the time I got her back in my chair for her re-do, it was a full 18 days from the day I first did them. Aside from working about 50hrs/week (give or take) as a full-time hairdresser, she also has an active social life... and the morning of her appointment with me, she had unpackaged & assembled two new salon chairs, then broke down the boxes for recycling.
During the box-breakdown, one of her nails' GelColor peeled off. So, she got a good 18 days of wear (Shellac would be peeling one her by day 12 or 13, unless I double-top-coated). After she declared, "I LOVE this stuff!", I also confirmed the color choice. She said, "This is actually closer to my favorite OPI shade - Thrill of Brazil - than the Shellac was." Um, yeah... actually, it's a dead ringer for the regular polish with the same name, but, she's sold!