Depends on what you want to do for hosting. There are some companies who will only host sites that they manage the domain name for (ie it's all part of the package). Other's don't care. I'd run it by your hosting company first. if your popping your own servers out into interwebworld, then check with your ISP too. Aside from that anything that seems to have the right deal. All they really have to do is fill out the form and hold a DNS entry somewhere.