I have the Meprolights.
The first thing that you would notice is how much bigger the "dots" are, compared to the stock sights.
Also, I like the fact that Meprolight had the forethought to smooth out the edges on the muzzle side of the rear sight (the side of the sight that is facing the front), so the sight doesn't tear up your hand on a fast slide grab/rack.
The only modification that I may make to the Meprolights is to open up the rear notch just a little bit, to let more light in, but other than that, I LOVE THEM.
It also helps that the Meprolights are quite a bit less expensive than Trijicon and others.
P.S. Sorry that I don't have pics, I really should have taken a pic of the stock sights for my own comparison.