I have been thinking about buying a SLR-106FR as my local gun store has 3 in stock. What should I look for to ensure I pick out one without the feeding issues that some of these rifles have? Is there a certain range of serial numbers? Or can you tell by the muzzle brake? I know on the 107FR, I have not seen issues with canted sights for 107FRs bought with the ak-74 style muzzle brake and not the flash hider.