How important they are depends on how big a jump you have between chainrings. I imaging they improve shifting quite a bit on a compact double with a big gap. They would be superfluous with something like a 45-52 because it's going to shift quickly and easily anyway. I actually haven't ridden anything with ramps and pins, but they should allow you to get away with shifting under somewhat of a load and being generally sloppier with your shifts. And they should make wide-gap doubles and triples a reasonable choice rather than a miserable choice. Guess you'd have to ride a specific combination with and without ramps and pins to know for sure. If you can find an unpinned chainring with a good return policy (Suginos are available) try it out and see how it shifts for you.