Looking into this as well. I think it is needed. My JK slides on wet rocks and loose stuff sometimes and other big rocks and trees come within inches. I am looking at all the different options- not as many for the 2012 yet. I like RokMen for example, but they have had a hard time designing one for the 2012 due to the redesign of the JK.
I don't know but I had a long conversation with them. Their stuff is awesome but they have been trying to design sliders and rocker protection. It may be the sliders they are having trouble with. I was going to stop by soon and chat with them. Maybe they will use my JK as a prototype and give me a deal.
I guess a lot depends on what you plan on doing with your jeep. I don't do a lot of rock crawling, so I went with the stock Rubicon sliders and added the ACE Rock Rails. Never had a problem with that combo and no body damage. The ACE rails were easy to install, great customer service, lifetime warranty, and compared to others I looked at, not that expensive.
If you are not going to be driving around bigger rocks, that will be a good setup. I don't want to lose much clearance under the sides so am not going to run the ACE sliders. Looking for other options but have not found any I like yet.