I once had a mistake with a wrong username and a name being 'pushed' to the wrong person. Now I like safeguards like the ones that Moniker has. Because it isn't much once you know your codes, but it's impossible for someone to give the name to someone else.
Nothing can be easier than Fabulous. Moniker can be a goose-chase the first few times. Go-Daddy is fine if you have all of the contact info (ALL of it).
It is not possible to be an easier push than Fabulous. You enter the new User ID and the names...then press send. Maybe there are a bunch ties, but you always need the new User Name/ID and the names, so it can't be any easier than the way Fabulous does it.