My experience is that if it plays, I do not attempt to return it. I have had LPs that were warped so badly they would not play without throwing the needle from the groove. The vendor has kindly replaced these titles for me without having to return the defective LP.
Many warped discs will play just fine. Life's too short to hassle over a disc that will play, eventhough it may not appear ruler flat.
Just this man's opinion. YMMV.
Mark