While you may be right for some RMAs, the vast majority of returns I read about here have been DOA, total dead drives within a short time frame, and weird problems such as clunking, refusal to open/close, spin up and down trouble.
I actually never have read of a person who sent an RMA because of a bad scan and the one (out of three) RMA I sent due to poor burn quality was scanned on my Liteon.
I just feel that BenQ has had to cut cost so much that the consumer winds up being the final quality inspector. Not to beat up BenQ as everyone has cut costs. It just seems to be more of a problem with BenQ right now.