I've never been too convinced that these are little more than cosmetic.
Never wanted to spend the money on them for a couple of reasons...
I'm not sure they would hold much of the bike off the deck in a spill - most pics i've seen have still resulted in fairing damage, less damage but it still needs repairing so where's the saving?
Also seen what happened to an engine mount on a gsxr6 when the mushroom dug in and carried the impact force through the bolt to the engine case! Freak occurance? Maybe, maybe not.
I just take my chances without them. They might save you some repair bills or they might cause a few more... make your choice!