Whether fixed or adjustable does not matter so much as the sight picture they present. Adjustable sights generally present a very good sight picture with a black faced rear notch, a flat topped rear blade, a tall straight sided, flat topped, black front black blade and the distinctive picture makes for very good, consistent alignment. Very few fixed sights present such a good picture. Most fixed rear sights are just a shallow, rounded groove in a semi-rounded top strap which makes it very hard to get a sharp, clear sight picture with consistent point of impact, especially with nickle or stainless guns. And I'm not even speaking of older fixed sight revolvers which often had fixed sights barely even visible to those of us with less than perfect vision. I once had an old 1917 S&W revolver in .45 ACP with fixed sights I had "re-worked" with a large brass bead front and a rear notch filed to a large half-round groove and after much tinkering to get them both just right, I could set the whole bead into the half notch to zero with 180 grain bullets or pull the bead down so that its top was level with the frame top for 230 grain loads and I shot that gun pretty well. But that was ten years ago and now I don't shoot any open sights very well. I now prefer the small, light weight, "tubeless red dot" sometimes called reflex sights and shoot better with those than I have shot any handgun in many rears. All in all, I like fixed sights on a carry gun because they are light, low, and rugged and one seldom really aims a defensive weapon. For "sporting" use, I find I just shoot better with the sharper sight picture presented by adjustable sights, the "adjustability" being of less importance than the sharpness of the sight picture. But for that use I now much prefer the aforementioned compact red dots because they present the sharpest of all sight pictures short of a scope.