Let's have a few names here and then we can even run a Poll. I will start with a few: 1. Tucows/OpenSRS 2. Godaddy 3. Namecheap 4. ENOM 5. Registerfly 6. Network Solutions 7. Domainsite
My only choice is NameCheap because they make it a breeze to transfer domains. GoDaddy has a better pricing package but requires more information in order to do a push.
MORE4LESS: $0.89 off .com registration YAFFASPECIAL: $0.90 off registration and renewal (works with .us extension)
I've only used Network Solutions (back when they were the only one) and Goddady. I like Goddady, so I didn't turn to any other registrar since.
As a domainer, I have to deal with all registrar's but I prefer domainsite. I think registerfly is an enom reseller.
For me, Domainsite is a little complicating to use. I am currently moving my domain names which I bought through sales from Domainsite to Namecheap. Basically consolidating them to Namecheap and The Planet. I like GoDaddy too because of TDNAM which provides an extra avenue for selling my domain names. Basically, anything which I would keep for good would stay with The Planet (the only issue is only existing customers can have accounts) and to Namecheap so allow for easier transfer. I've heard warning about going with Registerfy, where domain names goes missing. I would probably avoid buying any site using them. Not sure how easy it is to move away from them. I don't like Enom because since I am not a reseller, if I were to renew the domain name, it would be at a ridiculously high renewal cost which is out of sync with reality.