What is the difference with the modems you can buy and the ones that are supplied with your broad band?
Would I improve my wireless connection with a shop bought one?
The hook with using a different router is that if you are using the ISP one, any problem and they own it. If you use a different router then in my experience, the ISP will say "oh we don't support that router, you should be using ours" and the router manufacturer will refer you to the ISP.