Godaddy is the cheapest for me, no one else is as cheap, so I like that, and I like the folders and the tools. But godaddy is far from perfect so anyone who posts they are perfect is probably an employee at godaddy (that applies to any registrar recommendation - dont trust posts that are too glowing).
Godaddy has too much upselling. I think upselling is fine for the general user but why do that for accounts that are bulk users? What bugs me is that godaddy refuses to put in the right tools for the bulk buyer. If someone has over 1,000 domains then godaddy ought to have: a longer timeout, a direct path to the cart on purchases, and faster DNS updating (instead of sitting on their own PPC for hours and hours - godaddy is, IMO, STEALING income by their abusive dns setup; you get stuck on their ppc so easily, in several ways).
What i do: I buy .com at godaddy; I buy .net and .org at Moniker since Godaddy is VERY expensive for .org domains. Moniker has a very fast user interface now, fast dns updates, and is relatively easy to use.
But Moniker does not have all the features of godaddy, and Moniker seems to never change anything. Never any new features. They ought to hire a programmer some day. Moniker could potentially be the best registrar if they ever decided to add a few features. I could give a list.
In fact if one registrar were to list the very best features at each registrar, and implement them, it would be fantastic; but no one does.
Enom has a very fast dns update, the fastest I have seen, and I like their folder system the best. But they lack certain other features and do not have the best price. Their support, like Moniker, varies in speed - sometimes fast, and sometimes, just takes days. godaddy never takes days, they are always fast response. I dislike certain registrars a lot that dont have bulk tools, or have hidden modes you have to learn. I dislike fabulous, name.com, and really most of them. Maybe I am just not 'used' to them. I dislike 1and1 quite a bit, and of course the old RegisterFly was beyond bad; I think they are reborn under some new name, definitely avoid.
Godaddy wins just by being the largest, for Pushes: it is likely, for any domain sale, that a push can happen between buyer and seller. That is nice. For moving domains from registrar to registrar, only Enom has helped me move it faster - the registrar can directly approve the transfer, after you have done your approvals, *if* they they want to; godaddy and moniker refuse to do this for me, but enom will (on ocassion).
Summary: I tell people: use godaddy wins for .com and anything you plan to flip soon; Moniker for .net and .org; Moniker for bulk search on a lot of different TLD (Enom used to have bulk search for many different TLD but got rid of it). I also like, for escrow, just two companies: Escrow.com and Moniker escrow. I have not used Sedo escrow (the one time I tried, recently, they never followed through), and I would never use other, smaller/startup type of escrow services - your money is too important, just stick with Escrow.com and Moniker Escrow.
Kevin