Hi,
Still bangin' your head about this I see...
To request some additional care in the Quality Assurance process is certainly not a bad thing to do. As a DIYer, I too received DOA / defective products over the years, and faced the same time consuming, frustrating process as others pointed out - contacting the supplier, sending the unit back, wait for them to look it over, come to the conclusion that I wasn't BSing them, and then reissue a replacement product.
If you are of the mind that no one should be powering your subs but you, that's more than ok. You can request that I do a physical inspection of them before shipping. That should rule out the obvious faults...
Best regards,
Mark