The first iteration of Vaquero often shot low, which was generally deemed good, because one could file the front sight to adjust elevation. I believe I did that to mine. It was assumed that tall front sights were intentional by Ruger, so they could be easily filed to zero them. I dont know if thats the case or not.
If the fixed sight guns shoot to the side, and its not shooter error, the barrel can be turned in or out a bit to correct it. Its not hard for a gunsmith or amatuer with correct tools to do. The fixed sight guns look cleaner and more old time, but overall, the adjustable sighted guns are nicer for the gun crank that may change loads over time for whatever reasons.
Many of the adjustable sighted guns needed the rear sight raised way too high to be practical, I lost the elevation screw on one from the holster pushing the sight down and there being no tension on the screw. Fortunately it was in the holster (which was good, since I was camping alone in the Utah mts as a jr high school kid), but I didnt know where it was elevation wise after putting the screw back in. I fixed that later by lowering the rear sight to a few clicks off bottomed out, filing the front sight down to zero, leaving a little adjustment in the rear to lower if desired later. Ive done most of the adjustable sighted Rugers the same way ever since then.