It just been lanuched so reviews haven't been seen as yet. I've never used any protection on my cameras as I don't feel the need for it, even though I go out regardless of the weather. If you go rock climbing or other risky pursuits then it may be a wise move, if only to protect the camera body from scratches, but I doubt it would help if the camera fell down a rock face.
if there anything like the silicone covers for mobile phones they will leave rub marks on the camera body
although they do give some protection they come with there own problems
on a mobile phone they tend to mark the back of the phone not a great problem but if your trying to keep it completly unmarked these are not for you
saying all this i have no experience of the camera silicone covers only the phone covers