I finally got over lvl300 and had 4 exotic engrams. Decrypted them and got 3 of the same armor pieces and a the sniper I already had. Every one was under 300 light (and yes after the first 2 chest pieces I left the Cryptarach and came back to break the cycle up). So, I thought maybe it was becuase I got them before I reached 300. Then and bought 2 gauntlet engrams from Xur. Decrypted them and they were both the same Gauntlets and both were under 300. I thought they were supposed to start decrypting to 300+ once you broke the light barrier. Not to mention the whole getting the same item over and over again... Am I missing something here?