i don't own any screen protector yet, but these are my impressions from research and from examining my friends' phones
let's get one thing straight. none of these dental dam style protectors are going to save a phone from damage dropping it on concrete; even a 12" drop. Especially these nice heavy and fragile smartphones that we have. we need some realistic expectations here.
the purpose is to protect against keys, coins in pocket, dirty dashboards/glove compartments or tables that we like to store our phone. Maybe a fingernail stab when using the touchscreen. maybe setting it down on the curb/floor to play ball.
all these protectors might be 1 time use. in the videos they look pretty jacked up after they are 'punished'. of course they are immediately peeled off before showing you the phone spared of damage (without showing the dead protector)
Zagg -
Thickest w/ self healing, highest level of protection for these film type protectors (they take a dremel to it and i bet it isnt self healing from that), best grip, attracts pocket lint, probably good warranty and customer service due to
Most expensive, heard it can peel off at the edges, yellows over time, rubbery feeling not optimal for touch screens, orange peel effect (early versions)
PhantomSkinz -
Easiest to install, thin (like a condom), silky feels great for touchscreens, most invisible/best looking, minimal protection**, average warranty (it's handled by a 3rd party)
One time use protection/not self healing (once damaged, it's done - should protect the phone for the first 'incident')
StealthGuards -
Free right now, i heard it's like phantom skinz but thicker (so maybe like polyurethanes lol).
Probably no customer service, no frills, no fancy box, attracts oils/prints
i personally ordered the stealthguards to try it. i have minimal expectations.