Cubase 9.0.20, windows 10 1703 (installed in 2015) Stable as rock!
Plugin alliance,SoundToys, jbridge - no issue, also as many others plugins, updated to lastes versions.
Audio processing - no issue
Rendering - no issue
CPU spikes/peaks - no issue
Crashes - never got
One issue is GUI - but, Steinberg already working on it, so in future with every new patch we will se new GUI fixes(i hope)
I’m pretty sure 80% problems happened because: Unstable Pluging’s, background processes from other software (antiviruses,daemon etc.), and corrupted system files