Very nice and simple. But that's quite an expensive tld you've got there. That's going to add up over the years. Unless you're using a much cheaper registrar .st domains are about $75/year I think.
Actually, they're not that expensive. The .st TLD is maintained by Bahnhof, a Swedish internet provider ( they are actually pretty cheap. Check out www.nic.st , they cost about 45USD/Year there).