OK, well then let's clear up some misinformation first then. Three dots or two or one has nothing to do with accuracy. The accuracy of a particular set of sights has to do with the width of the rear notch compared with the width of the front sight. A set that leaves very little light on either side of the front sight, when centered in the rear notch, will be more accurate. A set that has more light on either side of the front site, when centered, will be easier/quicker to obtain a sight picture.
Also, the dots are not used to line up the sights, just acquire them. The proper sight alignment is with the top of the front sight aligned with the top of the rear. Since the dots are the same actual size, the front appears smaller when sighting down the gun. This makes it difficult to use them to align the sights.
So, for my own use, I prefer the three dot set up with a slightly wider rear notch. I'm a defensive shooter so, I find it easier to acquire the sights by seeing the dots in a line in my peripheral vision. Hard focus on the front sight and my shots hit the spot I'm aiming for.
Having said that, my preference is not set in stone. If I bought a gun with a two dot setup, I don't think I'd be hot to change it out.