I had mine done about 6 months ago now when (no word of a lie, there were bits of the rock between the screen and the scuttle panel when he lifted the old one out) a rock flicked up from between the rear wheels of an lorry and went through the bottom of my screen.
The fitter had a bit of a fight with the wiper arms on mine as they seem to have corrosion welded themselves to the splines so it took a bit longer than he said it would usually take but it took just under an hour all in. He did say though that i couldn't drive the car for 2 hours afterwards and he reccomended i didnt drive it far that day, Certainly no vtec.