Would it be fair to say some highlights (like number plates) seem a bit blown out in the night footage? reading a plate would be of prime concern for a cam.
You are right, at night ( also in the evening or cloudy day ) numberplates are "blown out" in the scenes where cars speed are different. In the scenes where your car speed is close to the front- or side lane moving car speed ( almost synchronised ), or you stopped in traffic, then as you can see from video samples, nubmerplates reading is quite clear. If in front of you- or side lane car speed is different than your car speed, then numberplates are getting "blown out". This rule applies to ALL dashcams.
Also big role plays numberplates light reflection and what type of headlights bulbs are used. You may read here:
Reading License Plates at Night. HID / Xenon, standard bulbs
Below is simple explanation of what I was trying to say.
I have stopped before traffic light. Front and right side car is also stopped, you can read their numberplates. Left lane car was passing me with a speed around 25-30 km/h and their numberplates are "washed out", as you mentioned earlier. But I must point out again - this rule applies to ALL dashcams that are out there now, no matter if its 50 or 500 usd. Within present technology and hardware used in dashcams, you can not get a better result than that.
One more example, similar to the previous one: centre car is stopped but from right side line car was moving.
Below you may see side lane car moving at the same speed as my car, so we can see numberplates. As soon as our cars speeds had changed, - I could not read his numberplates from dashcam any more.
Another similar scene.
Below is an example where front moving car speed was same as mine, so numberplates reading are very clear.
