I have a 15" powerbook g4 and love it. Don't worry about weight they are relatively light even my PB with an aluminum case is less weight than my 15" core 2 duo dell.

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2006 BMW X5 4.8is Lemans Blue/Beige/Dark Maple
-Nav, Comfort Seats, Heated Steering Wheel,
Rear Airbags, AUX Input
2009 BMW M3 Space Grey/Black/Carbon
-all options