This DVD blanks are not recommended. When burning ISO files (selbs created backups, typically 4.4 GB) with two burners under Windows (Roxio Creator) or Linux (K3b), at speeds of 4x or 8x are on average about 1 / 5ths of DVDs over (error when verifying the data, writing runs without error by). I do not recommend the purchase. Update 03/2015: because other DVDs were at least equally poorly tested, I again attempts a new charge Verbatim: we behold at about 20 fired blanks no fluke! You have to live with blank DVDs so well that some batches are faulty or not with their own burner harmonize (-> appreciation to 3 stars).
