I would worry about the price difference. TRUE, it won't have BMW inscribed on the glass, but as long as the glass looks clear and is the same thickness, it shouldn't be a problem. Make sure there is no warps in the glass, in other words, make sure that the glass doens't show warped images in some areas. You should be golden.
<span style='font-size:8pt;line-height:100%'><span style='color:blue'>1998 BMW 323is Coupe, Black
18" M3 Hyper Silver Rims
2 12" Rockford Fosgate Subs; Sealed
1.0 Farad Capacitor
800 Watt 2-Way Rockford Fosgate Amplifier</span></span>