I think a few years back, maybe 2003, they stopped having requirements. As far as the best place to register I am not sure. I believe I have a few a CDmon and some with EuroDNS, but I have not compared prices recently. I have a few renewal e-mails in my in box I need to take a look at. Wish I could be more help, hopefully someone will chime in here and shed some light on where to get the best deals for .es.