Ok, so having just invested a fair amount in a Sony Reader PRS-600 (Touch), getting a protective layer is thought by some to be a good idea, so I bought one of these FX-AntiReflex protectors.
This arrived loose in an ordinary window envelope, no special packing except the multi-lingual install cards (two of them) folded around it, plus the receipt which provided the delivery address - posted from Germany. No damage though - it arrived in good condition. You get a small lens cleaning cloth (like for reading glasses, but only 5cm square) to remove grease marks from the Reader, if needed.
Applying the film is not without its problems:
First note, be careful once you start to peel off the backing as any dust, lint (even from the supplied cloth) or fingerprints will easily stick to the adhesive side of the protector, so handle by the edges only. I doubled-over the backing film so I could keep a hold without leaving finger prints on it. This also meant I could peel the backing off as I placed the film down.
Secondly, unless you have the patience of a God, you will struggle to remove all bubbles. I used a large glasses cloth to rub the film surface down as I slowly applied it to my Reader, but had to lift and reset it several times - and it is still not perfect. For me, this is limited to some small bubbles at the bottom edge where I started applying the film, which I can probably live with.
Thirdly, beware that you don't tuck the film in under the edges of your Reader body. I have ended with my film set very slightly under the menu panel at the bottom. This leaves a small gap unprotected at the top of the Reader screen (about 1mm). Possibly handy for getting a fingernail under it for removal I suppose - it doesn't interfere with reading so have left it.
Contrary to other peoples comments, I have not noticed any significant drop in touch sensitivity - page turn "swipe" motion with finger/thumb works just as before for me. Stylus is unaffected - handwriting/doodles work just fine as well.
There is a slight reduction in glare, but not a huge amount, so don't expect this to work miracles.
My main interest in this product is to prevent accidental scratches on the screen in the early days of ownership. The actual Reader screen seems to be really quite robust. It doesn't seem to show up finger marks either, so unless you are looking for the "anxious new owner anti-scratch protection" factor like me, you may not really want to bother with this or any other type of additional layer. I'll try to remember to update this feedback after some reasonable usage period has elapsed.