Not even the latest most expensive routers are perfect..
I recently picked up a Belkin N1 and although its a cracking router (with free Tech Support!) it still suffers from signal problems in some parts of my house.
I decided to take it back to the shop (Staples) and swapped it for the Linksys WRT300N but as it turns out, the linksys is even worse!
I would recommend you try the Belkin N1 as once I had upgraded the firmware and optimising the settings I was able to transfer large files between machines all over the house which should mean the signals are good enough for most things (HD streaming etc).
The only things I don't like about the Belkin N1 are that it has to be stored horizontally and the blue icons on the front (which have replaced the standard green LEDS) are too bright and can't be switched off.
Anyway, here's some links to some recent router reviews and CNET have some speed/range comparisons...
http://reviews.cnet.com/routers/belk...-31864345.html
http://www.pcpro.co.uk/labs/156/draf...roduction.html