In BS6 gun metal grey you will get dual channel Abs, alloy wheels, tubeless tyres.Signals dual channel abs only we get.
KTM 390 Duke will not get any changes to its engine. There will only be cosmetic changes and feature additions.
Gunmetal Grey is a matte finish, whereas the silver color is lustrous. It all depends on your preference. Personally, I like the look of the lustrous finish better, as you can make it look really ...