The factory slider bar (for lack of a better name) is a separate piece. Not idea on price, but it comes off with two bolts. The same two bolts that hold on the Yamaha crash bars and aftermarket skid bars. I can't see how they'd be too expensive. Just heavy duty polymer sliders.
The real benefit of crash bars come when the terrain, on which one is crashing, isn't a smooth tarmac surface. That also being the surface type where one is more likely to be crashing in the first place. The factory slider bars stick out only a very small amount past the plastic shroud directly above it. If you were on even a normal gravel road, the shroud would likely drag and get scraped up, much less on a rocky trail. Just something for us to keep in mind as we consider or select crash bars. To me, I want the crashbars that stick out the furthest that anyone makes. I don't care if they don't look as good because they stick out so far. I care about crash protection because I'll be trail riding this beast. When I go down in uneven terrain, the further the crash bars stick out, the more likely the uneven ground is to reach the shrouds.
On a side note, I won't be replacing the side panels for every little ding because that would probably be monthly, if not weekly. That is one reason I'm happy with the U.S. getting the black panels. I figure scrapes in that plastic will be less noticeable than the silver coated panels getting the silver scraped off to reveal whatever color plastic is under the silver coating (presumably it's black plastic).