I use iKlear...
http://www.amazon.com/Klear-Screen-...ie=UTF8&qid=1373600788&sr=8-1&keywords=iklear
It seems Apple dumped them but it simply works and does a great job, plus a single kit can last like forever too. I'm still using the one I bought 3 years back since I'm not obsessively cleaning and mine doesn't get that dirty.
I agree that the cleaner lasts forever. I'm still using Apple Polish, the cleaner I bought for a MessagePad 2000.
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