I don't normally write reviews of my purchases, preferring to leave them until I feel I can be really useful in a specific way, and I think I can do that with this product, especially for anyone who has, or is thinking of purchasing this for use with a Raspberry Pi, or anyone else who is concerned about potential issues with RF range, and the problems some people seem to be having with this remote control.
There are a 'lot' of poor reviews of this remote purely down to issues with poor RF range. I can confirm that 'out-of-the-box', and used as instructed, there are often issues with the little receiving unit not being capable of picking up a good quality signal. I have experienced this myself, and thought I'd bought something that was almost unusable in my intended way, to control my Pi from a decent distance across the room.
I can tell anyone that has had this issue, or is worried about this issue enough to warrant not buying the product, that using the small USB receiving unit on the end of a short USB extension cable will solve all issues that anyone is having with limited RF range. I bought a cheap-as-chips A-male to A-female USB extension cable, for literally 'pennies', and it's solved all my range issues at a stroke. There seems to be some issues with poorly screened PCB boards, of which the Pi seems to be guilty of, and the simple method of moving the USB RF receiver away from the circuit board solves any range issues at once. I can only presume that anyone having similar issues in other flavours of media-centres or other PC's are having similar issues that can be solved with the same method.
In terms of raw numbers, before the USB receiver was moved from the Pi my range was limited to about 1m, and it was fairly erratic even at just the 1m range. After putting the USB receiver on the end of my short USB extension cable, I can still have excellent RF control at the 5m range, which is at the limits of my room. It may work well beyond that, and there's no reason to think that it shouldn't, but the change in range and accuracy of the mouse-pad movement was dramatically better as soon as I began using the extension cable.
I wanted to put this solution here to help anyone already having this issue, but also to help stop people being put off from buying this absolutely superb product if this one issue was the reason for that. It's a brilliant remote, especially for the Pi, and for the sake of spending another quid on a short extension then it should continue to be seen as the great product that it is.
I hope this review is useful, and that it can help people out.