My house is very tall and I was having trouble receiving the wireless signal at the top of the house from the wireless router at the bottom. Deciding between upgrading my router or getting a repeater, I opted for this. What the Siemens repeater does is to act as a middle man between my computer and the router. It sits in the middle of my house and passes on the signals from the router to the computer and vice versa.
I only have positive things to say about this repeater. The setup was very easy and it did not matter that my router was made by a different firm (BT). It will work with WPA security and has drastically improved both the signal and speed of the wireless internet for the computer at the top of my house. It has made things possible which were not before such as video streaming from BBC iplayer.
Finally, the repeater is fairly small and discrete so it doesn't look out of place really wherever you put it. If you are having signal problems in parts of your house, I would definitely recommend this.