I love that it's easy to use, fast customer service (even though they're not always available) and their prices are great! The only downside for me right now would be being able to access my account through mobile devices or via computer without logging in first.
Not sure if this will change when more people sign up but currently have no other website/registrars where you can do all of your business from anywhere at any time so this has been helpful. If anyone wants an inexpensive way to register domains then definitely give them try. They make registering simple enough for everyone even those who aren't tech savvy yet don't feel intimidated by doing things online.