I just got a set. For the most part, I love them - they are very easy to pick up, but I do have a few minor nitpicks:
1. You lose about 1/8 inch of sight radius versus the factory sights because of the length of the front sights. It can't be helped - tritium vial + FO = a really long front sight.
2. I wish they had drilled some ports into the sides to let more light in, and from different angles. I know that a combat sight really needs to be i securely, but just a pair of small ports on either side of each sight would have helped tremendously without compromising structural integrity. It's not a big deal outdoors under daylight, but inside, the fiber optics only glow if the gun is directly underneath a light source.