I was in 2 minds about declaring it....
I did, insurance did go up... But I'm bloody glad I did.
Ended up getting a replacement windscreen on insurance about 18 months ago due to chip from driving on the M4. Swapped the glass no problem via AutoGlass but then we had major issues recalibrating the instrument cluster. Lane Assist, Curise, Auto Dip Headlights - all work on the camera/sensors at the top of the windscreen.
Was passed from pillar to post between insurance, AutoGlass and VW about "who was going to deal with it". Insurance tried saying it wasn't covered because of the vehicle stance "not being factory"
To which I pointed out that I had specifically declared that I had aftermarket suspension/lowering.
Had them bang to rights at that point. They had to get a specialist company to recalibrate the vehicle and I was advised it was "very expensive"