Most wireless routers are built around a small selection of chipsets from specialist third party manufacturers -- so the performance differences between most retail brands isn't that great.
The extra price for Netgear, Linksys, D-Link and the well known retail brands can be justified by lasting customer support.
Here in the UK for a really cheap* good router I would choose a secondhand Netgear DG834 series model -- these are plentiful because several large ISPs issue them for free and they get dumped as customers change suppliers.
Though some contain custom firmware which will only work with that ISP, the DG834 sections of the Netgear support site include a utility intended to wipe corrupt firmware -- which has the handy side-effect of wiping ISP custom code so that you can download the latest Netgear retail firmear and update the unit.
* And when I say cheap, I mean just a few dollars.