While I hate to be that guy I'm going to be...
The rain is actuallypretty realistic if you have ever driven in total darkness with heavy rain you will notice it shows up as white lines on the drops which are lit up by the lights and makes visibility very short. This is what they are trying to simulate.
While it's not perfect it's better than the drive club rain shown, which doesnt affect visibility but does look nice sliding across the window.
I tried to find a video on you tube to demonstrate this but most are on streets with backlighting which means you don't experience the white lines of the rain but I can tell you for sure heavy rain in total darkness does look similar to this. Though I agree the fact it goes sideways when you go round corners feels a bit off.