Right! But, you must keep in mind that there is both lateral and verticle movement inherent in the horizontal SXS barrel design, that is not present in a verticle design. SXS barrels cause movement toward whichever side the barrel sits, then there is the rise, also. I have had a lot of experience with O/U double rifles and have found that, for the most part, the only change to POI is verticle...but not always. It seems that the soldered together barrels are the trickiest. Some stay put, while others confound me. Most stay close together and just shoot high or low.

Those SXS's go all over the paper, but in the pattern as I described. Again, this isn't carved in stone, but is a well founded generalization.

For some reason, SXS's are more sensitive to different bullet design and composition within the same bullet weight than are O/U's. I have no idea why. Maybe its just my own particular experience and not necessarily so, in general.