I don't know if there is any advantage to transferring your domain name to another hosting company... that is, if you purchased the domain name from a hosting company. Transferring a domain name and changing DNS servers are two different things. If you have hosting at Company A and are planning on getting hosting at Company B, you will have to change the DNS servers or you won't have a site to show anyone. Transferring a domain name is transferring the account you used to purchase the domain name, such as an account at GoDaddy, Directnic, and various other resellers to another reseller. If you purchase the domain name through your hosting company as part of a package deal, you might have some problem transferring it or you might not. That will depend on that particular company. Long winded answer, I know but I think I covered your points and probably several you didn't ask for, lol.