Have a lawyer? Have $10K to hire a 'power and component expert' to provide testimony that absolutely it is confirmed that the PSU caused the HDD failures? Ready to wait 10 or more years in litigation to get the money back for the drives, as no one ever is liable for data loss (except businesses)?
Really just because 'you' say the PSU caused it doesn't mean squat. You got proof positive evidence the PSU caused it, and not because you OC the board, not because you hooked it to a faulty electrical outlet, or that your local power grid on the days in question overloaded the lines trying to compensate for lower voltage in another neighborhood, and so on and so on.. Well you get the idea, any thing can be the culprit and just on YOUR SAY SO they are to blame NO they won't.