I've had my lower for over a year. No problems and I like the factory trigger pull on mine. Olympic ARs did have problems many years ago when they first came on the market. They are top notch now and as good as any major brand. I hear they have good customer service, but hopefuly I will never have to call them :wink:
I can think of only a couple thousand rounds my brother and I have put through my Dad's Oly Ar-15 A2 since I was 10. Had an interesting slamfire issue after maybe ten years of use, but it was quickly fixed. In my opinion, one of the best inexpensive Ar's out there.