Both would read ok at first then one stop reading any disk. Both would come up with write errors using clonedvd burning ty dvd-r did not have +r to try. I tried them in a windows 7 and xp machine and these were both computers that worked fine with other drives. Newegg was good enough to return all my money and I replaced them with LG that work great and they are on sale for the same price. I could have just got two bad drives but they both we very light which makes me wander how well they were made. Had I know that they were newer models with a new chip and with the 1.04 firmware I would have waited a while. It could just be a problem burning -r disk that they will correct later.