Those temperatures are about where I would expect them to be at with a cooler of that sort, it'll be a deal cooler typically if you're gaming on it though, those Cinebench figures for an all core load scenario are an extreme, they really give you a worse case scenario, so you're not likely to do anything that will make your CPU run hotter than that. One thing you do have to bear in mind though is that under a gaming load your GPU will be kicking out heat and this will heat up the CPU aswell to some extent so although the CPU itself isn't generating as much heat the overall heat load of the system will be higher it'll just be distributed differently, airflow patterns will affect this aswell, point being you 'might' see similar temperatures in reality under a heavy gaming load not so much because the CPU itself is working as hard but because the ambient temperature in the case is much higher because of the GPU.
I would say your temperatures are fine and nothing to worry about at all and I'd just get on an enjoy.
Just as a side note, the 5800X shouldn't be compared to either it's predesessor the 3700X or it's successor the 7700X in terms of temperatures really, they are all quite different, the 3700X will typically run quite a lot cooler and the 7700X is a different kettle of fish entirely, if you use the out of the box settings it will sit at 90-95c 'by design' and just clock as hard as it can within that envelope 'sort of'' where as the 5800X does not do that. However you can use 'Curve Optimizer' to influence this quite a lot should you wish to.