Surprisingly for MI's normal level of quality, they had a few tilting problems with their new Iron Dot style rear sight mount. They claim to have now fixed it. You can get an upgraded version if you already have one and if you are now interested in buying an improved one they are in stock.
Hat tip to Shooter521 at INGO.
They also have an interesting new flash hider that has TGI BART style spikes and they claim it reduces recoil.