Eh, even then, you're much better off quickly reading up on what beats what. You should make the decision on what specs you want before you go looking in stores. Also, it's not a linear score. Something might need to be twice as fast as something else to get .2 higher. In other cases, not. It's too unreliable.
Re OpenGL, AMD is usually much better, but it all depends on optimisation. For certain OpenGL programs (and OpenCL Programs) the vendor has worked with Nvidia to make it better, but from what I've noticed, when Nvidia is better, it's by a small margin. When AMD is better, it's by a massive lead. I couldn't tell you for Intel, but I don't believe it's too bad for openGL. Have a look at some benchmarks of programs you intend to use.