You should define further what you expect for distance shooting and hoped for accuracy. How far, and at what level of accuracy...
Troy sights are fine backup sights and they new front version with square post is more precise than the round one. But the rears are not adjustable for elevation and there are no optional front posts in different widths if you really intend to shoot long and accurately.
The KAC 600m read is a very precise peep for a flip up, but it has no close up (larger) aperture. And the KAC rail folding front, while a nice and small, lihtweight backup sight, does not take standard AR front sight posts, so you have only one option there too.
If you limit your long range to 2-300 yards, or expect only to hit steel gongs, etc at longer ranges, either of these will do. If you have more precise aspirations you will want to define your goals and buy accordingly.