It's cleverly done to look like so but the reflections are updated every 10-15 seconds instead of something like every 0.2 seconds on low (which makes it stutter) and perhaps in real-time on high (can't notice any stutter at all, like with it off). What you are seeing on reflective surfaces (cockpit and car bodywork) as you drive along is a constant reflection map taken at some point in the last 10-15 seconds. If you look carefully, you will notice the reflections suddenly pop in new reflection map. It's usually quite unperceivable but occasionally it is obvious, such as when the reflection map is updated as you are driving in a shaded area of track and then you drive out into a bright area of track and sometime later the reflection map updates and you notice the pop-in effect of the new reflections. I hope ISI can tweak this with some sort of gradual fade between the two? Because the performance loss is too great for high, low sucks and off is perfect apart from the pop-in effect.