I like that this is an affordable way to manage your domain names, it also makes changing registrars simple as one will change their account information at another provider (it does have some security issues though).
It can be quite difficult for new users of domains with no tech experience or who are not computer savvy so you really need someone experienced in managing web properties such as yourself if having problems/failing etc! We use them mainly because they offer free DNS hosting which saves us money but we would consider other providers too since there options seem better than ours (we only do about 500-1000 unique visitors per day!). Our main issue has been transferring our website over from GoDaddy when switching up was complete - very time consuming process compared against others' ease of transfer processes where sometimes even 1 hour could save many hours later down line (I know what i'm talking here!).