Aperture does hide everything in a package. I am now running Aperture and LR, just to see the differences. My Aperture library is almost twice the size of the files in LR4. I do like seeing my real files in LR.
After running both, I find Aperture's interface much better. I also like the way Aperture knows which focal point on my camera I used and shows it on the photo.
LR does much better at noise reduction and, of course, lens correction, which Aperture does not have.