Thanks for testing this, Paula!

I cannot talk about rendering entire scenes, because most of the renders I did with Vue 8 so far were skies.
I also found that the render times (on skies) was not increased compared to Vue 7.

Regarding clouds there are several factor influencing render times besides the render settings and the atmosphere quality:

One of those factors is opacity.
The portions of the cloud layer that have full opacity/no opacity are rendering a lot faster than the parts with semi-transparency.
For example, if you have "massive" clouds with a sharp density falloff (especially when adding sharpness) they`re rendering relatively fast.
However, with a few exceptions, like some types of cumulus, this will make your clouds look less natural (although even the "sharpest" cumulus clouds still need a bit of softness, otherwise they tend to look too solid).
I mean, when you look at clouds in the real world, they most of the time have a very smooth density falloff. You can achieve this natural look in Vue too, however it will increase render times.

Daniel1705, it could very well be that one of the reasons why it took 10 hours or more to render your clouds was because you had this second layer with low density clouds.

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