I have been worried about iKlear ever since the first "staingate" display replacement I had and the "Genius" at the Apple store asked what I had been cleaning it with. I told him iKlear and he specifically told me to not use it on these newer displays and to only use water and a microfiber cloth. So, I followed the instructions on Apples web site and did exactly that and then it occurred a second time on that same computer. So, no evidence that iKlear was ever to blame, but they were adamant about not using it.
Which was a shame, because I had just purchased a new bottle. But when I posted something about that, there was a forum member who wanted it/used it on an older model and said he would be happy to take it off my hands if I didn't want to use it, so I shipped it "free to a good home."
So now I just use the utility BigMacGuire mentioned, water to slightly dampen a spot on a microfiber and as little pressure as possible to do the job.