Ozone basically gives you the atmosphere editor from Vue, but inside the C4D environment. Unless there have been significant improvements to the atmosphere editor for Infinite, which as far as I know isn't the case (in fact, as far as I know it is exactly the same as in Vue5E), there wouldn't be much difference quality-wise. Ozone does allow you to tweak setting inside C4D and check their effect on your scene. If you stick to Infinite, you will have to switch back and forth between the two apps, and probably need to reimport a skydome several times to get things right.