To put this thing into perspective, I would not mind starting a gunfight with a revolver, SA or DA, as I am confident of placing the shots. After five, or six, though, if the fight is still happening, something has to be done about it, right quickly. The advantage of a DA revolver or semiauto pistol is that they require LESS MANIPULATION at reloading time. Most autos have the additional advantage of holding significantly more rounds. ("Less Manipulation" is a Clint Smith term; gotta give credit, and he stated this in regard to defensive single action sixguns.)
Once the SA sixgun is empty, I would want to reach for a second weapon. Know what? I usually carry two handguns now, anyway, and the second one is usually a full-sized fightin' pistol, like the first one. (There is nothing "compact" about a P229, even if the barrel is 3.9" in length; a mere one-tenth of an inch does not a compact make.)
A sixgun, with over 4" of barrel, really shines when shooting at distance. The balance of any SA sixgun, with 4-3/4" of barrel, or more, makes it a better "pointer" than most handguns; pointability matters most at short range. So, the SA sixgun DOES have a couple of advantages. Sometimes pointability and long-range ability will be more imoportant than the number of round in the gun, and sometimes the ammo capacity will matter more. Perhaps the best of both worlds would be one sixgun and one double-stack autoloader? Of course, this would only be feasible for those willing to tote two substantial pistols. (Yes, revolvers ARE pistols; look it up.)
As for concealability, an SAA rides quite comfortably on my hip, and the drape of the cover garment can hide an SAA at 0330 just as well as a double-stack; actually, BETTER than the double-stack. The SAA-sized grip frame is actually quite compact, the the balance point of the sixgun is well down inside the holster.
In summary, I can conceal an SA sixgun well enough, and it rides comfortably. Its superior pointability might allow me to STOP a close-range fight before ammo capacity becomes an issue. It long-range shootability, due to that beautifully long sight radius, might allow me to STOP a long-range fight before ammo capacity becomes an issue. I am far from helpless when toting such a sixgun.
I am NOT recommending that anyone tote an SA sixgun for personal defense, OK? I don't normally do so myself. But, hmm, I wonder if USFA will make a run of sixguns in .40 S&W, to match the chambering of my duty/carry SIGs?