It's the dns resolutions. It's taking an average of 5 seconds for the server to solve Amazon when doing an HTTP request (even via Lynx). That's what is making the bot so slow. We are working on it. But, we'll have to wait for the response of the people at our server provider tomorrow.
But, yep, doing a request directly from the ip takes an average of 80% less than when going with the domain name. So that's it. :-)

Emiliano