I bought a couple of keys, one for Windows 11 Pro and another one for Office 2021 Pro+. The delivery was supposed to be instant, with a button that is enabled after 5min once the payment was done. Well... despite I received the keys and they worked perfectly fine, the delivery is not instant nor done within 5 minutes... it took more than 3h to get the keys. The most frustrating thing is that the seller was online in the help chat and he didn't answered any of my messages. The difmark help chat is also useless, the only thing they told me is to wait until the sellers answer. I don't think that I will use this site again unless I really must to.