I've been using Joker.com for so long, my first bill might actually have been in Deutsche Marks.
I mainly stay with them because it just works, but also haven't seen an option out there so much better that it would be worth the minor hassle of changing.
But you might want to look at one of the comparison charts people posted here (though I don't see Joker on those) and see what services you want (whois hiding, dyndns, etc.).
We've made our choice, and we're sticking to it.