Let the User choose which ISO Download

Wubi is an astonishing easy tool. It gives the Windows user a full and easy Ubuntu experience, so many guides are arising. But every guide I read until now suggest to download first the ISO, to avoid an x64 ISO been downloaded.

I believe it would be great (though very easy) to add a simple drop down menu, so the user can choose between "Autodetect" and "... (x64)", "... (x32)", "... [else?]". I don't know how the ISO is choosed right now. The list of available versions could be downloaded before the first (and only) screen, in order to keep the installer updated.