I have been wearing Essie Ridge Base Coat for the last year or so. I was fascinated by the way it fills in the ridges of my nails. As a base coat, it works wonderfully. I just don't know what took me so long to find this one. Ya, I think two coats certainly does a better job in filling the ridges if you were to wear it by itself. I wear one coat with two applications of nail polish and a top coat. I'm pretty happy at the smoothness of my nails. The cost of this nail filler is $8.95 which is quite reasonable. Of course, where did I get it, you guessed it, Shoppers Drug Mart.