I am very new to Krinkovs, but I've owned a wsar-1 (7.62x39) for a few years now. I am thinking about trading my romy for a Krink. A couple questions. What is the effictive range on a krink (5.45x39 I think thats the right caliber) verses a wsar-1 (7.62x39)? With the origanal style flash hider, can I still put a bayonet on? Does the flash hider screw off? I live in MI, do I have to register it as a SBR?