We have a test of Wisestream H.265 here which explains what settings do, but the short version is:
- Wisestream dynamically controls compression on the scene, so moving objects are less compressed and static/background areas are more compressed, which lowers bitrate overall. In our tests, the "high" setting cause a lot of artifacting on background objects, so be careful with it. That may have improved with new firmware versions.
- Dynamic GOV varies the I-frame interval, so it will be short when there is activity in the scene and long (up to 160 frames, if I remember correctly), when there is no activity, which reduces bitrate.
All that aside, by nature you cannot make settings on the Wisenet Q and a Hikvision camera the same, because Hanwha does not use a true VBR implementation. They only set a maximum bitrate, then float average bitrate somewhere under that, like Undisclosed Manufacturer #2 mentions. But this results in both bitrate and compression/quantization varying. See Sony and Samsung Breaking VBR for more info on this.
Hikvision, by contrast, fixes compression and varies the bitrate to keep compression steady. So the max bitrate you set in a Hikvision camera is maximum, but bitrate will generally be much lower than that.
So if you are comparing the two by setting both max bitrates to the same value, it won't be a fair comparison.
All that being said, when we've tested the two head to head and attempted to arrive at the same quantization level to make it as standard as possible, Hikvision has frequently been lower. But I'd hesitate to say always, depending on what camera model you're looking at, how close the fields of view are, and other settings.
What models are you testing side by side?