I have a project I transitioned from v5, now running in 6.0, and the rendering updates are just extremely slow. Once it’s displayed, panning and rotation is fine - it’s building the 3d model that is just so slow to make it pretty much unusable.
The same project in v5 rendered within 5-10 seconds, while in v6 it takes more than 5 minutes. Worse, it hangs the whole program while it updates.