I love nail polish and i certainly love OPI ! I love that they come in many shades, so options are open :) always good to have a wide range of colours although my favourite one is the "mod about you". I wear this on my toe nails all the time. I feel like for my skin tone thats the best colour and it lasts for weeks with the top coat and even without the top coat actually. They are easy to put on and dries off quickly aswel. The nail polish is quite thick so you dont usually need to do many coats unless you prefer.
The only thing that gets to me is that it tends to dry up or get thicker which becomes hard to put on. The texture of the nail polish doesnt stay the same after awhile like other nail polish.
It is pricy but doesn't stop a nail polish lover to buy them :)
As an ex nail technician I mainly have nail polish brands that my old nail spa stocked (Essie, Creative, Orly) but I own a couple of OPI polishes as they have a great colour range and farmers stock them so convenient to buy. When I was pregnant my husband painted my toes and he would only use OPI because of the fantastic big brush. If my husband can do a great job painting nails with OPI then I'm sure that most people can!
I apply like other nail polishes with a base coat, x2 layers of colour and a top coat. The varnish goes on well, gives good coverage and easy to apply. The bottle looks nice, is easy to hold and the polish lasts as well as other brands I have used.
Tips: Make sure to use a base coat to prevent staining and help to make the polish last for longer and a top coat for longevity and shine.