I added a second linksys router today because my iPad signal was low (one bar) in some spots of the house.
On one of my linksys routers I loaded the DD-WRT rom because I was told it would make it easier to manage two routers on one network. I do like it better, but the stock rom is just as easy.
Then I read a post that said to use WPA2 not WEP and you may get a better signal.
http://www.blogsdna.com/9337/more-ipad-wifi-workarounds.htm I switched to wpa2 and now I have more bars on my iPad.
So I thought I would no longer need two routers, but then I found out my windows vista laptop does not like wpa2 on the DD-WRT router. I found a few blogs say a few people have a problem with vista, DD-WRT and wpa2.
My laptop works fine with WPA securty but the iPad works better
with the WPA2 so I will keep them both.