Touratech's is $136, and well worth it. The stock one is just a piece of plastic, and IMO could be easily defeated by a few pebbles. The one from Altrider is $146. Both will do well. The Altrider comes in black.
2009 BMW F800GS, Olive Drab
2006 Ducati Sport 1000, Black
Custom built Ducati GT1000 Scrambler, Red