I've been using the protective film product from Best Skins Ever for quite a while on mobile devices like my Blackberry. I'd started off with using the same product made by The Invisible Shield, but found Best Skins Ever to be the exact same thing at a better price.
I ordered the full skin from the manufacturers web site, though they also offer a screen protector only package as well.
The product is a clear rubbery feeling film that as a slight adhesive backing. I've found that it does a good job of not showing oil, which made it highly desirable for things like cell phone screens, the lcd on my Canon DSLR camera, etc. It doesn't show finger prints much on the iPad which I'd expected based on my previous experience.
The slight rubbery feel has been nice because it gives the device a bit of a non-slip feel and does a good job of protecting from scratches. I don't have any trouble with dragging my finger across the screen - the rubbery feel is slight and, while there is some rubbery give to the product, it's surface does feel a bit slick when I slide my finger across it. The combination of grippiness and slipperiness is just right. The iPad full skin kit includes a screen piece that covers everything except the home button, a round piece to cover the home button, a full piece that covers the back, and then several pieces that cover the side.
Installation isn't too tricky but it does get better with practice. The first time I tried installing the stuff on a blackberry I got really orange peely looking results with a bit of ugly glue residue showing behind the film. The application process involves wetting the film and laying it in place, then squeegeeing the water out with a credit card. I found that applying much pressure with a card makes the film look a bit distorted. Pushing the water out with my fingers and a paper towel has gotten me the best results.
Even with what I think is a good install, I do see a bit of orange peel on the screen and have considered removing the screen protector portion of the film. It has remained in place thus far since I enjoy the protection and the distortion isn't bad at all.
I have used their product on multiple devices with great results and have been very happy with the product on my iPad