When migrating our company's 15 domains away from GoDaddy I evaluated around a dozen registrars. Our criteria may be different from yours. With millions of subdomains and tens of millions of user-generated pages, we needed a registar that would absolutely honor our rights as domain owners. This was our top priority. Our lowest priority was cost, though there was a reasonable upper bound on what we'd pay per year. Features are somewhere in the middle -- we didn't want or need lots of extras.
Our priorities were:
1. rights as domain owners
2. registar stability
3. control panel usability
4. extra features (DNS, etc.)
5. cost
Read your registrar's terms. See if you still want to save that $6 a year.