My 5.56 BLR was lasting with no issues in practice, but I don't bang it about all that much. The gears do not instill confidence. Also, the 5 round magazine and no chance of extension (someone made a 20-rounder for Savage IIRC, using a modified M14 magazine, but it's not going to work in BLR).
I have certain hopes for Bond's upcoming lever AR. It seems better architected than Fight Lite's implementation (which uses a gear like BLR).