I am still rather new to this, but not all Starvis sensors are Starlight.
I look at camers specs for minimum illumination.
For Dahua Starlight you typically see specs like this:
0.009Lux/F2.0( Color,1/3s,30IRE)
0.07Lux/2.0( Color,1/30s,30IRE)
0Lux/F2.0(IR on)
For Dahua non-Starlight Starvis here is an example
0.06Lux/F1.6( Color,1/3s,30IRE)
0.4Lux/F1.6( Color,1/30s,30IRE)
0Lux/F1.6(IR on)
Notice the magnitude difference in the amount the sensor can operate in without IR.
That said there are many things that can impact image quality, lens type, aperture of the lens all play a role.
That said for me I use several 8MP and 6MP Starvis non-Starlight and the IR illuminated image is very clean. That said IR illumination can reflect off of certain surfaces which makes it hard under some situations this blowing out the detail.