On my wife's 328i, I replaced the front grills with the one from 335 which has chrome on the front edge of each grill. I bought the grills from the local dealer at about $35-40 a piece. Can't imagine X5's grill be that much more expensive?

For what it is worth, I like the black grill and if I were to look at replacing it with another color, I would just paint it. The black grill, once you take it off, is pretty much useless (the 328's sits on a shelf in the garage), so you might as well try painting your existing grills first. Worst case scenario, you can paint it black again.

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Currently driving: 2011 E70 x35i , 2011 E90 335d
Previous BMWs: 2007 E90 328i , 2005 E53 3.0i, 2011 F10 535i (6spd manual)