I'm not doubting that, but that's literally the first AR I ever built and it's been 100% operational for 16 years. I guess if it goes down...I'll just replace it. 
It's not my favorite, in fact its probably my least favorite...Just simply listing that I have one.
I'd "assume" the issues are more to do with different quality of mil spec parts. Working on a high quality part vs working on a low quality part makes a huge difference in how long it will ultimately last.
