The qques negative points / to check on the duration:
The placement of some keys may be difficult to remember, especially if like me you use a keyboard "classical" work ...
I expect a lot of battery life promised by the manufacturer! I doubt go until end of 3 years, but if it already exceeds the year and a half, I'll be satisfied.
And remains to be seen if the finish will be as good in a few months / years, whether the keys are commener to fade and / or become "smooth", if you see what I mean.
Anyway, a great cheap little keyboard.
EDIT: After 2 years of use (23 months to be exact), I still have not changed the batteries, Logitech thus not lying about the enormous autonomy!
The keyboard is always nickel, no trace of wear, no erased key.
The "weird" positions which I spoke in 2011 at the final NEVER asked me worries.
Anyway (twice), I am very satisfied with my purchase ... of it two years ago :)