Yeah I've read that too, and 1080p will allow you to save more on the memory card
I might check out that polarizer, someone else has given me some suggestions too...
- Put the camera as close to the screen as possible
- Angle it down (like you said)
- Cover the dash in a dash-mat (which I'm not interested in)
Let me know what you find out about the polarizer! Keen to get one but cant be bothered making one