I own this game. I have not changed out the back glass and wont change it either. I think it is pretty cool. I also own a Gold Wings and i changed the backglass on that sucker as soon as I had the chance.
I think the gameplay on Raven is good. The shots are hard though. I also like the 'realistic war sounds' the machine makes. I have seen so many Demolition Man and Dracula machines that this is a breath of fresh air.