This is my first post here.
I also received my first flip open folder today and it is the Urban Trapper cocobolo. First I have to say it's amazing. By far the sharpest knife I ever had, at least for cutting paper. And the looks and general feel of quality.
Well the scales actually has a bit of a ribbed contour length vise. Though mostely toward the sides. After seeing some YouTube vids I get the impression that how pronounced they are seems to vary a bit.
When it comes to how good grip you get I don't think on this particular knife the actual scales means that much. The handle is so thin that my fingers goes all the way around it, so the fact that the scales are thinner than the frame and that the back of the frame is open is what gives me a good grip.
I also like the looks of the g-10 version and I'm seriously thinking about buying that to (partly because I'm not sure if I ever will be able to get the knife so insanely sharp).
Either one you buy I think you will be happy, to me it's a true treasure.