Thanks for asking for my opinion. I have been using InkTonwerStore for a few years now. All-in-all, my experience has been good. Shopping on your website is relatively easy given the number of different cartridges that are available. The order arrives promptly. The cost is much better than purchasing through the machine manufacturer. I have had only one cartridge fail. From the onset, it colored the entire page yellow every time. I changed cartridges and that corrected the problem. I attempted to contact customer service to obtain "return order" instructions, but could not get the phone to answer. As instructed, I left a return phone number but did not receive a return call. After a similar experience on a second attempt, I gave up and decided to take the loss. I figured that you saved me much more than the cost of one bad cartridge. All this to say, that customer service could use a little work, but all else is satisfactory.