I've had the phantomskinz ever since I got the device a couple months ago.

Smooth: I like the feel better than the screen itself. To me, its just the right amount of resistance. If you use the stylus or a fingernail it slides really easily, using your finger it kinda depends on how much surface area you are using, meaning that when you use the tips of your finger (like when doing a normal swipe) it easily glides but if you put the whole pad there is a decent amount more (slowly scrolling through a list/webpage) making it move very deliberately.

Tough: haven't had any issues, but really haven't had any scares either. Its held up for a few months of intermittent stylus use and looks just as good as the day it was first installed. It did have a low-height fall onto a semi-sharp edge and it created a scuff that buffed right out.

Clear: Unnoticeable. Well, unnoticeable on the actual screen. You can definitely see it at the edges (partly my fault on the install), but its not instantly noticeable and again I'm just referring to the edges, 100% clear on the actual screen itself. I didn't use my phone without the protector that long so I can't comment on whether it has affected brightness at all but even if it does the screen is still plenty bright for me (I suspect it does not have a noticeable effect).

For me personally, despite the tricky install (prepare to screw it up the first time...luckily they send 2 protectors) it has met and exceeded my expectations.