I'm also shopping around for this and would like to know people's experiences. I'm willing to buy the expensive clones but then there is always that nagging doubt on the back of my head that... what if the site fails? then it would be a waste of money... lol. I know... if only things were easy and guaranteed, right? Anyone has some review of what they like/don't like about their script? From what I see pinterestclones is pretty good but for the annoying CSS that loads all pins on the left side before spreading them across the screen. I also cannot for the life of my get the demo to pin youtube videos. It only pins a screenshot of it. I've contacted support about it and they say they have no problems. Maybe someone can try and let me know if they can/can't do it? My other tip is to take a really close look at the demo and admin because some clones have different features.
It might look like Pinterest, but it doesn't have the same functionality as Pinterest that you would find in a custom script