I bought the iKlear but found it to be pricey. Supposedly, according to the iKlear propaganda, it chemically treats the screen to be resistant to dust, dirt, etc. So far, that seems to be a bunch of hooey. So while I still use it, for day-to-day cleaning while out and about, it's the $4.95 eyeglass cleaning kit from Wal-Mart that includes 20 travel towelettes, a microfiber cloth, and a 1oz bottle of cleaning fluid that they will refill for free!
Well, actually, I take the towelettes and microfiber with me, the bottle stays home.