I don't know if they're my "favorite", but I have a set of Trijicon HDs on my PPQ 9mm. They do shoot a little low, at least for my preference. Instead of hitting to the top of the sight post like I zero all of my other pistols and revolvers to, they require a "drive the dot" sight picture, hitting somewhere near the top of the Tritium insert at 25 yards.
(Yes, it's a bit of a weird sensation trying to shoot small groups. However, when shooting steel, silhouettes and most non-Bullseye type use, it's been a non-issue.)