I've played around with several different protectors. My first XO installation went bad, but they gave me a free replacement (thanks XO) and the installation for that went much smoother. The clarity was pretty excellent and there was almost no orange peel effect, though if you turn the screen off and angle it to catch glare, you can see a subtle effect (but not a deal-breaker). What was a deal-breaker, for me personally, was that I still noticed the rubbery feel after several weeks of having the protector.
So I tried the SGP Flex. It's also a wet application, pretty identical installation to the XO, nice near-complete coverage as well (just as much as the XO). The bad is that the orange-peel effect is fairly noticeable when the phone/screen is off, but not so much when the phone is on unless you angle it for glare...it also doesn't deter oil smears as well as the XO. It does, however, have a great glass feel to it. For that reason, I'll keep it on for now. The XO was almost perfect except for the feel which, in the end, I found was pretty important for me.