I have always used SGP Ultra Crystal on my 4S. I ordered my Ultra Crystal for iPad a few days ago. My only concern is that whether the Ultra Crystal would work with a stylus (I ordered an iPen yesterday). If you are not using a stylus, then Ultra Crystal is the BEST out of the three. If you are using a stylus, maybe (since my iPad is not in yet... so don't know for sure.)
The Ultra Optics and Ultra Fine is known to work better with stylus since they have a antiglare finish that somehow makes the stylus more responsive. BUT Ultra Crystal MAYBE just as responsive... I can tell you when I receive everything and test them by end of week... 😀