Rather than take up space & time here, if you go to my thread on the Elcan Specter DR on the FN forum you can read how well Elcan addressed a minor POI shift on my new Specter DR mounted on a SCAR 16. In my opinion it is a great sight for it's intended purpose. Here is the link
http://fnforum.net/viewtopic.php?p=179791#179791