Unreliable. You are wondering if it's going to work half the time. Waiting for something that doesn't show up isn't the best way to serve the user. Frustration makes for loss of market share. I hadn't used it for days and when I went to download something it tried to tell me I'd 'reached my download limit' which sounded to me like an irresponsibly placed message in order to cover up some other issue stopping the user from accessing the promised service. At least be honest and tell people 'the service is currently offline, sorry'. There are other add-ons that do what this one promises and they do it reliably, so why bother sitting round wasting time, hoping it works?
Try this instead https://yd.3dyd.com/download/